hybridfree/eevblog-posts huggingface dataset:
Yamaha N-303D - Page 1
Forum section: electronics / repair

author: geobee
author_rank: Contributor
timestamp: January 01, 2022, 03:13:55 am
content: Hi all, have this unit on the bench that wont go into factory reset. It is in protect mode. Also, cannot get it to go into self diagnostic mode so I may be able to see what has caused it to protect. I have removed the main board and checked all the output devices, all checked fine. It is not a unit I am familiar with, the badge states it is a network amplifier. No HDMI etc, just a basic setup. The fact that it wont go to the diagnostic node, makes it difficult to know what may have caused the protection to kick in. It belongs to a gymnasium, so volume level may have been the issue. Maybe someone has looked at one of these units? Cheers. Geoff

author: bob91343
author_rank: Super Contributor
timestamp: January 01, 2022, 05:03:19 am
content: Get a service manual.

author: geobee
author_rank: Contributor
timestamp: January 01, 2022, 08:04:44 pm
content: I have the manual, and have followed the diagnostic procedure, to no avail. I do hear a relay latch, not sure which one/s, but the display is not coming up, so it makes it impossible to see what is going on.

author: coromonadalix
author_rank: Super Contributor
timestamp: January 01, 2022, 08:20:31 pm
content: Well the usuals checks areAll the power(s) supply rails have to be checked, starting from the mains ones into the small / sub ones going into the main boards, sub boardsSometimes, if you can remove / un slot / un connect some pcb's it can help troubleshoot problemsGot the service manual from the hifi engine (i have an account there) , you have the ac-dc board who has an dc-dc converter on it, an some regulators in the power amp pcb start there

author: mzacharias
author_rank: Frequent Contributor
timestamp: January 01, 2022, 11:10:47 pm
content: Quote from: geobee on January 01, 2022, 08:04:44 pmIf after this you can press the power button and hear another click (as if turning OFF) I would guess the -30V line for the display is out - or whatever powers the display, they've changed this on recent models.
YAMAHA P-45B Digital piano - standby switch fails - Page 1
Forum section: electronics / repair

author: raul320
author_rank: Newbie
timestamp: May 16, 2021, 03:36:40 pm
content: Hello,Few days ago, my digital piano Yamaha P-45B got an issue with turning on. power adapter worked fine, so i decided to open the case and dig a little bit deeper. After unscrew about 40 screws (!!), i've started analysing what is going on and found damaged transistor TR101 2N5551, so i've replaced it by similar one MPSA42-D.It seems to be repaired, but:- After connecting power adapter, piano is ON (as ussualy)- After pressing standby button for 2sec, piano will OFF (as usualy)- Then, when i press standby buttoon again, it won't ON (as it should)I don't have service manual for this model, but i found similar one - basically this part of schematic seems to be the the same:Now, can anyone explain me:1. how this mosfet switch works?2. How it turns on and off?3. What can be the reason, that it can't turn on again?

author: Vicus
author_rank: Regular Contributor
timestamp: May 16, 2021, 06:27:15 pm
content: The mosfet FT101 is the "switch". In order to turn on so the current can flow VGS has to be lower than -2, -4V. This is how I think it work: When pressing the on off button the signal PWSW goes to gnd and via D103 it lower the gate voltage so it tun FT101 on. After it turn on PSWD goes high so TR101 turn it on and this keep on FT101. At turning off PSWD goes away and at /PSWI a high voltage inhibite the PWSW signal so FT101 turn it off.It would be interesting to know who generate the three signal PWSW, /PWSI and PSWD.Now you have the multimeter in your have, have the right measerement in the right moment and guess what's wrong.
Yamaha PSR-4500 / X4500 keyboard memory pack? (+ROM dump) - Page 1
Forum section: electronics / repair

author: shakalnokturn
author_rank: Super Contributor
timestamp: July 07, 2020, 03:18:51 pm
content: After catching this early '90s synth in the dumpster, spending many hours cleaning all key contacts, washing the sediments of what looked like a layer of barn dust, cobwebs and animal fur with a high pressure cleaner I have a working keyboard.The upper keys panel with all the synthesiser adjustments is badly warped and some of the screw posts beneath are breaking due to the PCB's pushing them sideways but I can't see what can be done about that.Anyway attached a dump of the ROM in case it's of use to anyone.I would be interested in a service manual and any technical information on the cartridges that fit the "PACK" expansion slot.
Yamaha R700 Distortion and Oscillation Trouble - Page 1
Forum section: electronics / repair

author: Benji01
author_rank: Contributor
timestamp: June 25, 2023, 11:06:52 am
content: Hey Guys,well the Yamaha R700 is back. Last time I repaired the tuner and replaced the output STK modules.The receiver worked for couple of weeks than it stopped working. After opening the receiver it was quiete obvious what went wrong this time. Both STK modules died and some resistors burned.After opening the broken STK Modules it was clear that the output transistors failed. They failed probably because they where cheap knock-offs. The transistor dies are smaller than the original and the modules are missing both emitter resistors.So after a bit of research it was clear that I can't get any quality replacements for the STK1050II, so I found this thread on DiyAudio:https://www.diyaudio.com/community/threads/stk1080ii-devices.332605/So I decided to give the discrete version a try.Well the discrete modules work but they have a couple of small problems.If I use the R1/R2 as shown in the drawing and I want to set the quiescent current of the output transistors than the amplifier starts to oscillate at around 500kHz picture 12/13. If I replace R1/R2 with a 10K potentiometer and a 500Ohm resistor I can set the quiescent current without the oscillation.Now to the other problem. As seen on picture 10 and 11 there is crossover distortion and I can't get rid of it no matter of how I set the quiescent current.All transistors are with their gain more or less close to each other.Does anyone here has an idea of what I can do to reduce or get rid of the crossover distortion ?
Yamaha RX-1130 - Page 1
Forum section: electronics / repair

author: ttx450
author_rank: Regular Contributor
timestamp: September 21, 2021, 10:06:31 pm
content: Hi, got this from a relative to work on. Anyone know how to reset it I can't find anything so far?

author: bob91343
author_rank: Super Contributor
timestamp: September 21, 2021, 11:38:28 pm
content: https://www.hifiengine.com/manual_library/yamaha/rx-1130.shtml

author: ttx450
author_rank: Regular Contributor
timestamp: September 22, 2021, 01:10:55 am
content: Quote from: bob91343 on September 21, 2021, 11:38:28 pmThanks.. need to turn off my vpn and join hifiengine.org tomorrow.
YAMAHA RX-E600 - Auto turn OFF in 2sec after power ON - Page 1
Forum section: electronics / repair

author: 2X
author_rank: Frequent Contributor
timestamp: February 20, 2020, 05:25:58 pm
content: Hello, I have buy a used stereo receiver the YAMAHA RX-E600 with two woofers... the man that have it before told me that when the sound volume rises close to MAX it turned off automatically. I measured the coil of the one woofer and had under the half resistance compare to the other one. But now when I push the button to open it lights for 2sec the LCD and turns off automatically with no speker connected at all. I find the schematics and I measure power supply and indeed when I press the power button gives 4,7V to the relay driver but after to seconds gives 0V and the relay and the radio turn off. Does anyone knows what is this that find short circuit maybe and turn off?Pdf file - Pages 3 & 4At the connector (CB254) that is the signal "PRY" for the relay engagement I measured 4.7Vat the "12S" I measured 11.7Vat the DG I measured 0V (Digital Ground)at the "F1" and "F2" I didn't measure something and this connected to the transformer and I don't know what ishttps://youtu.be/hxInJFaXRGc

author: mzacharias
author_rank: Frequent Contributor
timestamp: February 23, 2020, 03:36:44 pm
content: This model predates Yamaha's more sophisticated diagnostic programs.You should check the output transistors for shorts, check for DC offsets at one or both amp channels during the interval before the power turns back off. Same with checking the various power supplies during this interval.It is also possible to apply power directly to the main transformer to troubleshoot internal voltages at your leisure. There are severe risks involved with this if you don't have the requisite technical skill.
Yamaha RX-V 596 RDS Receiver Buzzing Sound - Page 1
Forum section: electronics / repair

author: fermyon
author_rank: Newbie
timestamp: February 20, 2021, 11:40:56 pm
content: My Yamaha RX-V 596 RDS Receiver has a buzzing sound. The unit is approximately 20 years old and I obtained it second hand. I just noticed the buzzing, but it may have been there from the beginning.The buzzing can be heard on all speakers and the headphone port, but it is loudest on the front left (recording is attached). It becomes louder when connecting the optical input. At normal listening volume, it is barely audible. The volume increases with the main volume knob. However, it disappears once I am close to full volume.Service manual:https://www.vintageshifi.com/repertoire-pdf/pdf/telecharge.php?pdf=Yamaha-RXV-596-Service-Manual.pdfI also connected my "oscilloscope" to the speaker terminals of the left speaker and recorded the waveform.Without optical input: see first image.With optical input: see second image.Without optical input, there are pulses every 10 ms. With optical input, the pulses are wider and bigger every and occur every ~12.5ms with additional smaller pulses (not sure which interval).Due the 10ms pulses I first thought the power supply capacitors may be faulty, but since the frequency changes when the optical input is turned on, it seems more likely that the issue is in the decoder/electronics.I also tried grounding the receiver since its plug does not connect to earth, but that did not change anything.Is there anything else I can check? What do you think might be the cause? To be honest, I am not very knowledgable about this sort of thing.

author: ambrosia heart
author_rank: Regular Contributor
timestamp: February 21, 2021, 02:13:06 am
content: First thing to do is to isolate the audio path. See pm.Don't write too lengthy. No time to read composition. I am now playing a game. I wrongly chose Claire as first to play, leading to great difficulty in second play. I must start from Leon with no choice and play it from start. Oh dear!A good opening is a key to success, not only in troubleshooting but also in gaming.

author: SpecialK
author_rank: Regular Contributor
timestamp: February 22, 2021, 12:05:11 am
content: Well the inverse of 10ms is 100Hz. Since Germany is a 50Hz country, recification would create 100Hz products that the power supply capacitors are mean to filter. So I would look at the power supply section. Maybe find the regulator that powers the op amp circuitry. Look at the electolytics around the area.

author: fermyon
author_rank: Newbie
timestamp: February 24, 2021, 10:20:36 pm
content: Thanks for your suggestions. The issue (gradually?) disappeared while I was measuring an internal left channel pin. I might have accidentally connected it to the right channel with the probe, but not sure.

author: mzacharias
author_rank: Frequent Contributor
timestamp: February 25, 2021, 06:46:22 pm
content: I'd always suspect power supplies and ground paths first.'Scope the power supply rails for similar noise;Make sure all the grounds are confirmed good.
Yamaha RX-V1000.  Relays click. Back off right away. No panel display sometimes. - Page 1
Forum section: electronics / repair

author: Gringo
author_rank: Newbie
timestamp: April 20, 2020, 12:36:29 am
content: Greetings to all humans!So I'm finally getting around to trying to repair an old Yammy RX-V1000 5.1 receiver I bought from a thrift shop a few years ago, non-working.Symptoms:Press power button. Primary relay is audible. But, right away, it turns back off without any display or lights on panel.Regarding above, it appears in some locations I've tried to power the unit, it was successful in powering up fully in a commercial building (storage facility) where I stored this for a while. I guess it had better voltage condition that the receiver liked. But even that, the display still seemed a little dull. The speaker relays also clicked as well.Back in a residential home. It is doing the first symptom again. For Diag mode, however, if I hold down the "A/B/C/D/E" and right "Tuning/Preset" buttons while powering the unit, I can hear the primary and speaker relays click as if it were operating normally, but still no display (I didn't have a chance to try this in the storage unit to see if the display would light up). If I hit the power button again, the relays all click off like normal.For the moment, I'm trying to see if I can hook up a monitor or TV to it to see if it is outputting anything during diagnostics so I could access the menus.I hope I was able to give a good description of its behavior. I have a soldering iron as I do car audio installs, but board repairs I'm still a newbie at, but I am comfortable with attacking this issue.edit: In complete darkness, in diagnostics mode, I can see the red lines running through the display, but none of the characters are lit up

author: mzacharias
author_rank: Frequent Contributor
timestamp: April 20, 2020, 02:43:19 am
content: Starting DIAG in the protection cancel mode:If the protection function works and causes hindrance to trouble diagnosis, cancel the protection function as described below, and it will be possible to enter the DIAG mode. (The protection function other than the excess current detect function will be cancelled.)Press the “STANDBY/ON key while pressing those two keys A/B/C/D/E and preset tuning (right)At this time, keep pressing those two keys for 3 seconds or longer.If you do not hear the relay click back off, or if you determine that the internal voltages stay ON,you can proceed troubleshooting at your leisure.
Yamaha RX-V1800 acting strangely - Page 1
Forum section: electronics / repair

author: atunguyd
author_rank: Contributor
timestamp: October 26, 2021, 08:47:45 pm
content: Hi Wonder if anyone can help me debug this strange issue.I have an old Yamaha RX-V1800 which has started to act up - no real reason to replace it so hoping to try fix it.About 2 years ago it did have the no power on issue and I fixed that by replacing the C4 22nF 630V capacitor on the power board. Been working just fine since.Last couple of days I have noticed that the power button on the front panel will not switch it on or off (not the master switch but the soft touch power button) although it switches on and off just fine from the remote.I can live with that but tonight it started acting really strange - we were watching TV and suddenly the relays on the speaker boards started clicking madly. I switched it off and back on and it was working again but after a couple minutes the relays started to go nuts again.I thought it might be related to the C issue again so I removed and replaced that cap but still the same - switched on and off via remote just fine and relays start clicking. I also noticed that on some power on cycles there was no click from the relays and there was no sound coming from the speakers, just sound coming from the active sub woofer. On these occasions I needed to power it off (master switch or at the wall) and back on and it occasionally came right, but then started the mad clicking again.I confirmed that it is the speaker relay board that is clicking as placing my fingers on the relays I can feel them activating. It is also not just one of them, but sound slike all of them clicking on ad off. This makes me think it is not a faulty relay on that board (they would not all go together surely).Not sure where to look now so would appreciate any advice.ThanksAnthony

author: mzacharias
author_rank: Frequent Contributor
timestamp: October 29, 2021, 12:33:35 pm
content: Lots of problems with the tact switches on the front panel. Since they're in resistive ladder arrangements they can and do cause all sorts of issues.Pretty sure that takes care of your first problem (the power ON tact switch), maybe even the relay issue.
Yamaha RX-V2067 ground issue? [solved] - Page 1
Forum section: electronics / repair

author: czarlz
author_rank: Newbie
timestamp: June 28, 2024, 11:01:37 am
content: Hey everyone,I noticed that there are some people experience here with this piece of equipment.The story is like that:1 ) I bought it broken, shutting down soon after power up (protection)2 ) I found broken C1016 (100uF/35) in the feedback loop of the SBR channel, causing leakage and DC offset3 ) Then I found broken Q1096 (2N5551C) == no +LB voltage, i.e. no positive rail for the amp drivers4 ) The amp starts no without any problems, but..5 ) There is a 100 Hz humming noise in all the channels6 ) No sound from any of the channel7 ) The sound gets through the headphones though (without 100 Hz noise)8 ) Changing inputs takes no effect (I can see them changing on the screen only). By default AV1 is the only one which passes the signal.9 ) Volume level for the only working input in combination with headphones seems to be fixed, changing it takes no effect.Seems to me that I have two separate issues:1 ) Ground issue2 ) Input selectors & volume control ICs issue (IC741 & IC742)The thing which I find totally bizarre is the ground connection within the power amps. If I look at the schematic, the input stage (+ drivers) has a separate ground from the power stage ground. The input stage ground is common with the chassis and all the input RCA connectors, which I find OK, but then the power output stage ground (also speakers' "-") and the main supply middle/neutral point has nothing to do with the "signal/reference" ground. They put some components like R1310 (marked with purple in the schematic attached) to tie them together, but they are "no use". If I measure resistance between the signal/reference ground (marked with yellow) and power amp output terminal "-" (marked with solid green), I read 20 kOhm. How can the amp's input&drive stage work correctly with the power stage if they have no common ground?Will be super grateful for any of your thoughts.BR

author: Harry_22
author_rank: Frequent Contributor
timestamp: June 28, 2024, 08:14:00 pm
content: Hi!Check the ripple on C1105, C1106.

author: czarlz
author_rank: Newbie
timestamp: October 16, 2024, 08:49:32 pm
content: Problems solved!While fixing the drivers' regulators I had to unscrew the whole back panel, the ground connection between the back panel and the terminals was therefore not made. This is the place where the reference ground and the power amps outputs connect. I was missing this!Second issue with volume and input selector not working: by mistake I inversed one of the FPCs, precisely the one which was sending over the data from the MCU to the 2x R2A15220FP, which are the input selector and volume ICs.Problems aside, this is the most terrible to fix piece of audio equipment I have ever had in my career. Very badly engineered, I wonder whether on purpose?
Yamaha RX V2067 part - Page 1
Forum section: electronics / repair

author: skillsy1963
author_rank: Newbie
timestamp: June 05, 2021, 03:13:57 am
content: Hi Everyone,I am chasing a spare part for a Yamaha RX V2067 Receiver, it is the net pcb with the part number WU764300. The same part also fits the RX V3067 and RX A3000.If anyone has one I would be interested in purchasing and getting it shipped to me.Thanks

author: RayRay
author_rank: Frequent Contributor
timestamp: June 05, 2021, 02:52:06 pm
content: Is that the actual part number, or the one specified on the parts list in the service manual? Do note that these aren't always identical (and this can definitely affect your search results!) You should be looking at the part number on the PCB itself (usually it'd either be printed on it, or it'd have a sticker that contain it). Also, if I may ask, what is the actual issue with your receiver? How did you establish that it's that one particular board that's at fault, and have you considered the option of repairing it (diagnosing/replacing faulty components) instead of outright replacing it?

author: skillsy1963
author_rank: Newbie
timestamp: June 06, 2021, 02:19:43 am
content: Hi, Thx for the reply, That part number is the one in the service manual, the part number on the board is WU76430 so just missing the last 0. I had repaired a power problem on the unit and then the sound went, I ran the diagnostic and got it down to the second DSP chip on the net board. Also when I heat the chip up with the heat gun it works again for a day or so.

author: RayRay
author_rank: Frequent Contributor
timestamp: June 06, 2021, 03:08:10 am
content: Afraid I didn't had any luck finding itAnyways, what does it say on the chip itself? Could you provide an upclose picture of it?

author: David_AVD
author_rank: Super Contributor
timestamp: June 27, 2021, 01:33:18 am
content: Did you contact Yamaha for P&A on a replacement board?

author: skillsy1963
author_rank: Newbie
timestamp: July 17, 2021, 09:10:57 pm
content: Yes I did and they told me that the board is no longer available
Yamaha RX-V2071 (RX-A2010) Flash Memory - Page 1
Forum section: electronics / repair

author: Raff
author_rank: Regular Contributor
timestamp: August 03, 2016, 01:10:16 am
content: Hi guys / gals,I'm trying to repair a Yamaha RX-V2071 / RX-A2010 receiver.The fault is no sound, picture is ok.Ive narrowed the fault down thanks to the on board diagnostics to the "digital 2" board, it has DSP #2 on it.Ive tried reflashing all the firmware, but the process goes ok until its tries to verify and fails with error 0100.I have checked the voltages on the board and they are ok, and I can see data on the pins ok.I'm suspect of the flash chip that holds the DSP firmware, its a Winbond 25x40bvng.My questions before I go and maybe screw things up.Anyone had a similar chip go bad on them?I recall from old TV repair that similar chips that held the settings for TVs would often go bad.I have a couple of similar but 8mbit chips from Macronix.If I replaced the chip with the larger one and reflashed it do you think it would work?At this point I guess I don't have much to loose.Attached is a PDF of the schematic of the Digital 2 board.Thanks,Raff

author: Raff
author_rank: Regular Contributor
timestamp: August 06, 2016, 03:03:14 am
content: An update.I got my el cheapo programmer in the mail today that handles those sorts of flash chips, so I de-soldered the one in the Yammy and read it, erased it and reprogrammed it fine, I also tried the larger ones I had.The end result? Didn't make much difference except now I get error 0200 when I try to update the receivers firmware on verify.Looks like the actual DSP chip is faulty, oh well.I'm off to try and either source the whole little board or it will have to go off to an authorised Yammy repair agent it seems.

author: Raff
author_rank: Regular Contributor
timestamp: August 09, 2016, 08:07:20 am
content: Further update.I managed to buy the "digital 2" module direct from Yamaha Australia and now the amp works fine.Hope it helps someone else.Raff

author: Gregegg
author_rank: Newbie
timestamp: May 05, 2019, 10:01:24 pm
content: Hello Raff,I just want to thank you for posting this fix as it appears I have the same fault.I was going for the Speaker O/P relays but now realize that since all sound channels are off and all video and controls are working fine that my fault is likely the same.I have contacted Yamaha Australia to see if could obtain this DSP 2 PCB.I will update here if successful with purchase from Yamaha and is also my fix. Now to return the 30 odd screws securing the rear panel.Thank you again for posting.

author: Gregegg
author_rank: Newbie
timestamp: May 10, 2019, 05:57:26 am
content: Hello All, Yamaha supplied the Digital 2 PCB, replaced and all working fine. Hope this helps someone else
Yamaha RX V3071 HDMI no sound but everything else works - Page 1
Forum section: electronics / repair

author: skillsy1963
author_rank: Newbie
timestamp: January 30, 2021, 12:56:38 am
content: Can anyone help me with this Yamaha. Everything works except the sound on the HDMI inputs. As soon as I plug the hdmi cable in the speaker icons on the display disappear, when I remove the cable they come back. I am wondering if it is one of the hdmi switching IC's??Any suggestions?Thanks in advance
FIXED: Yamaha RX-V3900: high Power 1 - Page 1
Forum section: electronics / repair

author: NFG
author_rank: Newbie
timestamp: July 20, 2020, 03:35:58 am
content: You might remember me from theRX-V3900 with bad Power 3(but you probably don't).That hacky adjustment to the summing resistor has seen the amp run happily for the last 12 months, but now Power 1 has developed a fault. Normally 43-66, it shut down when it measured 67.Searching the forum, I foundthis thread. I'm sort of thinking that the answer to my problem is the same: any one of several dozen things could have gone wrong. I'm just lost for a starting point.I dunno if it's a clue that the PS1 readingjumped from 67 to 84since turning it on to maintenance mode?(paging @mzacharias)UPDATE 1:I measured all the voltages that PS1 monitors:+12(12.3): 11.84V-12(-12.1): -11.82V+5D2 (5.0): 4.97V+RY(12.0): 12.0V-RY(-11.8 ): -11.84V+5I(5.5V): 5.60VAll of those are virtually identical to the measurements in @pwkwong's thread linked above.UPDATE 2:My plan is to replace all five of the above resistors, and see how far that gets me*. If all the voltages are the same, then its the voltage measuring logic that's failing, right? Just so happens I'm out of all the resistors I need, so I'm off to the shops tomorrow.* Or maybe just the negative voltages since the reading is too high?

author: NFG
author_rank: Newbie
timestamp: July 21, 2020, 03:21:30 am
content: Holy shit I fixed it. ^__^I replaced R81 and R47, both negative voltages, and for good measure I replaced R44 and R45, the AC lines. Not sure which one(s) fixed the problem but I assume it was either of the first two.PS1 is now reading 54, which is dead in the middle of the spec (43-66).Many thanks to pwkwong, for treading the ground before me, and mzacharias for helping me through the first time this happened.And the rest of you beautiful viewers who can now stop typing up your lengthy replies of tips and encouragement. You're the greatest.
Yamaha Rx-V430 receiver error ps prt:021 D - Page 1
Forum section: electronics / repair

author: mrrcomp
author_rank: Contributor
timestamp: October 14, 2023, 06:47:07 pm
content: HII have a yamaha Rx-V430 it shuts down after a few seconds. If i check witht he "test buttons" i.e Main while Input selector and a/b/c/d/e/f buttons pressed i getPS PRT:021 D .I tried to do a search what the meaning is but can't find anything specific to it.Would appreciate any help in troubleshooting this receiverRegardsMeir

author: macboy
author_rank: Super Contributor
timestamp: October 14, 2023, 09:25:29 pm
content: I didn't find specific information about this in the service manual for this model, but in the service manual for the RX-V559 which I've recently worked on, it describes different protection codes:I PRT:000 ACurrent overload protect. Could be caused by a short circuit on the output terminals, or a low impedance speaker driven at excessively high volume.PS1 PRT:000 APS2 PRT:000 APower supply overload protect. Could be caused by fault regulator or some component excessively loading a power rail, causing it to drop too low.DC PRT:000 ADC detected on output. Often caused by a faulty output transistor in an amplifier, sometimes resulting from short-circuiting the output, which is usually caused by messing around with speaker wire connections while the receiver is turned on.TMP PRT:000 AOver temperature limit.The number 000 will increase with the number of times that each type of fault has been detected.In your case, this is likely a Power Supply fault detection. Check the various power supply voltages. If you identify one or more that is too low, then try to determine why.

author: David_AVD
author_rank: Super Contributor
timestamp: October 14, 2023, 11:06:05 pm
content: Not specific to this model, but check the resistors that that a feed from each of the power rails to derive the power supply detection voltage. Sometimes these go high in value so cause the level to be shifted outside of the normal range.The manual should list what the acceptable range is and there's usually an entry in the diagnostic menu that shows the current value. If the displayed value is too low, check the resistors that come from the positive rails. If the displayed value is too high, check the resistors that come from the negative rails. Sometimes the resistors for the AC sensing can go bad too.
Yamaha RX-V471 is powering on, but no output sound - Page 1
Forum section: electronics / repair

author: Mikaelin
author_rank: Contributor
timestamp: September 19, 2023, 07:45:21 am
content: Hello,Yamaha RX-V471 is powering on, but no output sound.I checked all in SELF-DIAGNOSTIC FUNCTION menu:Power supply OK.Power amplifier output voltage OK.HDMI loopback test OK.C1. DIGITAL P.C.B. CHECK - from C1-1. ALL to C1-8. EEPROM -> ALL OKNo errors were detected by the integrated self diagnostics.I performed then A7. MANUAL TEST"The built-in noise generator of DSP outputs the testnoise or test tone through the channels specified byusing the sub-menu" - > A7-1. TEST ALL"The test noise is output from all channels" - No sound on all channels.I checked the voltage on VCC+ pin2 of STK433-130K power amplifier - stable 54V present.A factory reset not helped.The power amplifiers seems to be good but I'm not sure how to check.The service manual with all schematics isherePlease help me to identify where is the problem.Thanks

author: max.wwwang
author_rank: Frequent Contributor
timestamp: September 19, 2023, 08:10:23 am
content: The link to the service manual does not work to me.

author: Mikaelin
author_rank: Contributor
timestamp: September 19, 2023, 08:16:23 am
content: Quote from: max.wwwang on September 19, 2023, 08:10:23 amCorrected the link. Thanks

author: Swake
author_rank: Frequent Contributor
timestamp: September 21, 2023, 06:33:37 pm
content: It has a speaker relays. Do they come on?Is there 'sound' signal on the input of the relay? if yes check if the transistors that power the relays receive a signal and if there is adequate power around that circuit. Page 102 in the linked schematic.If not continue tracing upwards the power module and so forth till you find the audio signal. I assume the noise generator is working and because of this going backwards should give quicker results, but of course the issue can be anywhere.

author: wasedadoc
author_rank: Super Contributor
timestamp: September 21, 2023, 07:59:56 pm
content: There is a common control signal to the 5 muting circuits just prior to the power amplifiers. Check that.
Yamaha RX-V573 Power Output Stage Repair - Page 1
Forum section: electronics / repair

author: irobot
author_rank: Newbie
timestamp: November 04, 2024, 05:42:52 am
content: Yamaha RX-V573 Home Theater UnitDislike these kind of problems. Replaced outputs Q2058, 2059, 2044, 2045.Triple checked every transistor, diode, resistor, and capacitor against other working channels. Everything OK, all measurements spot on.Powered up, and *poof*. Q2058 and 2059 gone. All pins BCE dead shorted.I've done many, many of these before. 45+ years experience.What am I missing?

author: Jeff eelcr
author_rank: Frequent Contributor
timestamp: November 04, 2024, 08:06:57 pm
content: Yamaha, check for open/ changed value resistors in strange places also have had other parts fail after checking them.Jeff
Yamaha RX-V583 DC Protection - Page 1
Forum section: electronics / repair

author: pbarker73
author_rank: Newbie
timestamp: December 31, 2024, 02:56:20 pm
content: Hi FolksLong term lurker, first post.I've got a Yamaha Rx-V583 which goes into protection mode when turned on. Bypassing protection the error is DC PRT: 000. Page 37 of the attached service manual suggests this is an abnormal DC output at the speaker terminal. Following advice from other threads here I've measured the voltage at the emitter resistors. All the channels measure 0V except SBL which measures 0.17V, so I'm guessing that this is the culprit. My question is, is it likely to be the output transistors - is it worth pulling the main board and removing them to check them? If not what would be a good next step?Edit - can't attach the service manual it's too big.https://drive.google.com/file/d/1r3LtY7z8kruw282SWtCtpTQzt4xsjmVl/view?usp=sharing.Thanks

author: Swake
author_rank: Frequent Contributor
timestamp: January 01, 2025, 03:28:06 pm
content: Might be, or another one, or even a passive component. Start with checking all the Q's and D's in in that area. Page 130 Zone 4-5 / C-D-EAnd also Q2005 on page 132.DC PRT: 000 -> the '000' part indicates that the voltage was 0 Volt. That is somewhat strange. You could also have an issue with the power supply of that SBL amplifier.

author: pbarker73
author_rank: Newbie
timestamp: January 11, 2025, 04:23:14 pm
content: Thanks Swake. Sorry it's taken me a while to get back to this. It's proving to be somewhat elusive!I've checked all the Qs and Ds in the circuit and all appear to be reading good.Guess I need to start looking at the passives.

author: Swake
author_rank: Frequent Contributor
timestamp: January 11, 2025, 04:46:17 pm
content: Can you measure the power supplies?If these read ok, do you have a scope to check the ripple on them?

author: pbarker73
author_rank: Newbie
timestamp: January 11, 2025, 05:46:26 pm
content: I've measured the supplies leaving the power board (operation 4 on page 98). They all seem to be present and correct. I have a scope, but I'm definitely still learning and haven't tried to measure ripple before.
Yamaha RX-V673 - can't turn on, protection fired up - Page 1
Forum section: electronics / repair

author: leniwiec
author_rank: Contributor
timestamp: January 21, 2023, 12:53:14 am
content: Hi All,I just replaced HDMI connector on digital input board and can't power on receiver. I try to enter self test mode using tone control + info + power button combination, and after 4th time it works. After unlock, receiver start to work. Every possible function works correctly, until I power it off. Then whole things start again.During hdmi port repair I disconnected digital input board. I wonder if I should execute some procedure to re-initialize this board or sth ?Is here anyone who have experience servicing this device, and can help ?

author: jeffjmr
author_rank: Regular Contributor
timestamp: January 21, 2023, 03:35:40 pm
content: Try holding down the power button for 10 seconds to reboot. If that doesn’t work, unplug the power cable for a few minutes then try the reboot again.I have had the same problem on occasion with my RX-V685.Jeff

author: leniwiec
author_rank: Contributor
timestamp: January 21, 2023, 11:49:27 pm
content: thx Jeff for response.Currently I solve this issue. The problem was faulty resistor R826, which is pull-down for I_PRT bus (which is responsible for delivering I PROTECT signal to main cpu). Visually there was no sign of malfunction on this part. Voltage on bus was correct. Only during detailed examination under microscope I saw little crack.It was very nasty fault, because when I measure this resistor, I push it with my probes and it start to conduct normally - 47k, but without pressure it go to around 800k. After replace, everything start to work normal.

author: jeffjmr
author_rank: Regular Contributor
timestamp: January 22, 2023, 04:33:59 am
content: Happy to hear of your successful repair.Did you accomplish this without a schematic?Jeff

author: leniwiec
author_rank: Contributor
timestamp: June 01, 2023, 08:52:41 am
content: No, schematic was essential to find this problem.
Yamaha RX-V673 - No Power - Blowing T2.0A Radial fuse each time power is applied - Page 1
Forum section: electronics / repair

author: ACRO
author_rank: Newbie
timestamp: October 22, 2020, 10:49:32 am
content: Good morning/afternoon all!Firstly, I am a newbie to electronics so please forgive me! However 2 weeks ago we had some issues (potential neutral fault) in our building (comprising of 26 apartments) that led to a number of electronic devices failing to power on. So far, I have managed to repair our 2 Sonos speakers which were relatively easy to diagnose and repair (blown capacitors and radial fuses).Next up is our Yamaha RX-V673, I was hoping to have a go at repairing it myself before resorting to either paying someone else to have a look. Upon visual inspection on the Video-2 PCB when power comes in to the system, I noticed that F3701 (T2.0A Anti-surge Slow blow radial fuse) had blown, as well as capacitor C3706 (KXJ 400V 68uF) which had a bulge in the side and lid. I replaced both of these and reapplied power, unfortunately however the fuse at F3701 keeps blowing each time in quite spectacular fashion (loud pop, smoke and flash).In the photos of the solder side, I had removed the safety capacitor at C3704 to test, however from my reading it appears X2 capacitors rarely fail. From what I can tell, it should not be too complicated to identify the issue as there is only a limited number of components that could be at fault - considering it appears to be an issue with actually getting power into the system.Unfortunately I am limited in terms of electronics knowledge and equipment (other than a cheap soldering iron and basic multimeter).Any pointers would be greatly appreciated!Many thanks,Adam

author: ambrosia heart
author_rank: Regular Contributor
timestamp: October 22, 2020, 11:52:16 am
content: See PM, just FYI. Don‘t post it.Tell me your result if you wanted.

author: mzacharias
author_rank: Frequent Contributor
timestamp: October 22, 2020, 02:50:19 pm
content: Diode bridge D3701 or switching IC IC371, I would think.

author: George Edmonds
author_rank: Frequent Contributor
timestamp: October 22, 2020, 11:23:11 pm
content: HiIf you have suffered a neutral fault in a large building which will be supplied with a three phase supply it is possible under some circumstances to have an incoming mains supply of up to 400VAC. No switch mode power supply will tolerate this, they will just virtually destroy themselves.About two years ago I tried to sort out an Office in London that the same had happened to, what I found was that the repaired items, which included high end photocopiers, even when repaired failed again within a short time.Unless you are very experienced with the repair of switch mode supplies, you say you are not, find someone who is, they can be very dangerous to work on as there some 360VDC at high currents present throughout the entire supply.It is very easy to get into a situation where the supply repeatably blows up and possibly spraying molten copper.George G6HIG Dover UK
Yamaha RX-V683 power issue - Page 1
Forum section: electronics / repair

author: EasyWire
author_rank: Newbie
timestamp: May 28, 2022, 06:21:00 pm
content: Hi,My house got hit by lightning. When I turn on the Yamaha RX-v683 the red LED flashes. I've bypassed the power protect mode by holding down the tone+info+ power and the receiver briefly flashes "PST PRT 158".After I get to this screen, pressing the screen 1 button to cycle gives the following:S4-1 System: 2.87S3-1 Preset: INHIS2-1 MDL:V683 255P2-1 1.PS2 158P1-1 DC: 51T4-1 1.PS2 158T1-1 RL 713D1D13H53MIf I do the test all, the speaker outputs do work (static). If I test individual speaker outputs I do hear a tone on each one (including FP L/R). I tested with one speaker and moved it to different outputs.Does anyone have any advice on how to troubleshoot this further, or know where I can get the service manual?Thanks!James

author: David_AVD
author_rank: Super Contributor
timestamp: May 29, 2022, 01:10:09 am
content: Service manual can be found here:https://www.hifiengine.com/
Yamaha RX-V765 Amplifier Issue - Page 1
Forum section: electronics / repair

author: irobot
author_rank: Newbie
timestamp: October 03, 2024, 10:49:11 pm
content: Yamaha RX-V765 7.1 Channel Home Theater ReceiverAfter replacing Q1055A and Q1055C (outputs) and emitter resistor R1153:-1.5V DC on speaker output, SL channel. Although the unit works, it should be near zero. Not comfortable leaving it this way.B+ and B- are where they should be at all points.I'm at a loss because I've checked every component and taken other measurements using good channels as reference.Voltages on other channels are just about spot on to what schema shows.I replaced Q1041, Q1048, C1034 with no change.Notes: Q1020, Q1027, Q1034 are for bias. Q1062 is a tap-off point for protect signal. Q1027 is physically attached to heatsink as temperature "sensor".UPDATE 10/04/2024: Fixed. Replaced Q1011 and Q1012. Although checked out OK in and out of circuit, these must have been breaking down with power applied.

author: David_AVD
author_rank: Super Contributor
timestamp: October 04, 2024, 02:27:01 am
content: There will likely be a dead transistor or resistor somewhere just before the output transistors.

author: suntime
author_rank: Contributor
timestamp: October 04, 2024, 09:16:58 pm
content: Hi,Check Q1020 & Q1011.
YAMAHA RX-V775 - No Stdby LED and no power up for service - Page 1
Forum section: electronics / repair

author: richtoy
author_rank: Newbie
timestamp: November 06, 2020, 02:06:27 pm
content: I have a YAMAHA AV receiver RX-V775 with a power fault.The standby lamp does not come on and it does not power on or enter any service mode.My fault is identical to the one described in great detail in Japanese on these 4 pages. Google translate the pages.https://ameblo.jp/amblog-minors/entry-12467816407.htmlhttps://ameblo.jp/amblog-minors/entry-12467816371.htmlhttps://ameblo.jp/amblog-minors/entry-12467816312.htmlhttps://ameblo.jp/amblog-minors/entry-12467816214.htmlAny ideas where to look next? The Japanese tech got no further...

author: ambrosia heart
author_rank: Regular Contributor
timestamp: November 06, 2020, 02:54:48 pm
content: Quote from: richtoy on November 06, 2020, 02:06:27 pmMicroprocessor does not work.You should troubleshoot standby boardthat is a circuit board letting AC inputted. You will see a standby trasformer here.

author: richtoy
author_rank: Newbie
timestamp: November 06, 2020, 03:20:45 pm
content: The symptoms and all measurements are exactly as described by the Japanese technician in the links.I have checked the switched mode PSU and all values look correct. The CPU runs but appears to be halted as noted by the Japanese tech.

author: ambrosia heart
author_rank: Regular Contributor
timestamp: November 06, 2020, 03:40:39 pm
content: Did you measure reset signal and +3.3M? They are in phase.Did you measure microprocessor waveform? If all voltages on standby board are OK and reset signal as well as microprocessor crystal waveform is correct, microprocessor is dead.

author: richtoy
author_rank: Newbie
timestamp: January 30, 2021, 10:21:32 pm
content: I have been busy with other stuff but have now got this Yamaha back on the bench.The crystal waveform is correct, 8MHzThe +3.3M and reset are both 3.3V from when the power is applied. Is this what you mean by in phase?What I have noticed is that after power is applied the standby light does eventually come on (after 90 seconds) and stays on for precisely 24 seconds and then goes out for another 90 seconds.This on/off with an off of 90s and on of 24s appears to carry on indefinitely. The period is really quite precise. During the 24 seconds that the standby light is on the amp still does not respond to any inputs.Anyone seen such behavior before?After examining the boards carefully IC4 and IC943 have been replaced after production but IC943 appears to function correctly for the 24 seconds that the standby light is illuminated.
Yamaha rx775 - Page 1
Forum section: electronics / repair

author: Kentakung1
author_rank: Newbie
timestamp: January 08, 2020, 05:37:07 pm
content: How to fix.Error. Code. Protect. Dc prt 75hHelp me. Please

author: Kentakung1
author_rank: Newbie
timestamp: January 12, 2020, 04:22:27 pm
content: I. Measure. At. R1225.140vWhy. Voltage. High. ??Help me. Please

author: pbarton
author_rank: Frequent Contributor
timestamp: January 13, 2020, 09:29:02 am
content: One possibility is that the large capacitor C1085 has gone short circuit.The bridge rectifier would then deliver it’s full output of 140V, across the other large capacitor, C1084 and R1225.Unfortunately these large capacitors are only rated at 71V, and consequently you should assume that C1084 has been damaged by the applied 140V.If correct, then both capacitors would need to be replaced as a matched pair.Disconnect the capacitors and measure them with whatever test equipment you have available.Another possibility is that there is a short between the -61V power rail and ground.Possibly in a different amplifier component, or even within the PCB.You should be able to confirm this with a simple resistance check.

author: Kentakung1
author_rank: Newbie
timestamp: January 14, 2020, 11:50:00 am
content: Now. I have. New problemR1214. Have. Burn.But. Can. Power on.Volume ++Have. ProtectI measure. High. Voltage at. Q1069. And Q1070 is 56 voltI check. Transistor. Ok

author: pbarton
author_rank: Frequent Contributor
timestamp: January 14, 2020, 04:18:29 pm
content: You still have the original fault?Do you have +61V and -61V on the two large capacitors C1084 and C1085?First you have to fix the original fault, before proceeding.You should have 3.3V at the base of Q1069 and the base of Q1070.But what do you measure?
Yamaha RXV 3900 D video board issue - Page 1
Forum section: electronics / repair

author: strandbiker1
author_rank: Newbie
timestamp: June 22, 2019, 11:56:58 pm
content: I have a Yamaha RXV 3900 (US version). I recently checked for new firmware and found that the current version is 1.25. The software in the receiver was 1.21. Previously, I used an USB stick and the .bin file to load the update. I entered "Advanced Setup" and "Firmware Update" then selected USB. The receiver indicates "Please Wait". After several minutes it does not show progress. I exited the Advanced Setup and re entered trying to the Internet method without success. The receiver shows 1.21 as my existing firmware version. I also tried the recovery mode without success.After several additional attempts, I took the receiver to the West Coast Yamaha repair shop (George Meyer AV) in Los Angeles. The technician said that after trying the recovery mode, that my "D Video" board was "bad" and that Yamaha has no replacements. From the service manual I found that the US version of the board (U) is WQ132200. I was unable to locate a replacement board or a salvage RXV 3900 to obtain a replacement board. This leaves me with attempting to troubleshoot the existing board. I know on other posts that cold solder joints can cause issues. From what I see in my attempts to load .bin file, that the receiver is not even seeing the updated .bin file.Any ideas from anyone? I have had no other issues with the receiver and the firmware update worked in the past and this is something new. I can enter the Advanced Setup and see the firmware diagnostics.Thanks in advanceSkip
Yamaha rxv-657 goes to protect. Help! - Page 1
Forum section: electronics / repair

author: strat1953
author_rank: Newbie
timestamp: December 24, 2020, 11:57:59 pm
content: its turn on then goes right to protect.i changed c405 but did not fix it. i also checked all the amp section transistors and the amps fine.if theres a yamaha tech that knows what or where the problem is or where to look,i will gladly paypal you to repair advice. you can also text me 480-703-9586 or email strat1953@aol.com thank you. i also have a 757 with the same problem

author: mzacharias
author_rank: Frequent Contributor
timestamp: December 26, 2020, 04:12:24 pm
content: Do you have the service manual and know how to use a multimeter?Most shut-downs on Yamaha's relate to regulated power supply issues (bad voltage regulator like a 7805, 7812, 7912, etc) or a DC offset on a single channel.Blown amplifier channels cause a much faster shut-down, so fast the display never lights up, and you only hear a quick single click.