Fluke 177 failed and need support to repair - Page 1
Forum section: electronics / testgear

author: Chinhdc
author_rank: Contributor
timestamp: December 26, 2021, 03:52:23 pm
content: Hi Gentlements,As you know, Fluke measurement equipments are always be the first technician choice, and me too. I have been using the Fluke Digital Multimeter model 177 for some years after putting the 8 years used Kyoritsu 1009 to the store due to some malfunctions and the unstable results.In a beautiful day, i took the Fluke 177 to measure its inside battery (9VDC), i turned the knob to right function and the probes is in right positions. Of course the measure result was nothing and i turned off and turned on (the purpose is checking the voltage of the inside battery whether it was good or bad because i often used continuity function that the buzzer used much energy that the battery exhausted quickly after a short time of replacing).After the measure, the Multimeter became failure. When turned on, changed into any function, the LCD display as attacted pictures with buzzer (Of course without probes) as picture from 1 to 3.I have browsed on Web to find help but hopeless.So, I would hope and highly appreciate any idea to solve the problem of my Digital Multimeter to be back normally.(Attracted pictures from 4 to 7 are inside of the multimeter for more details).Thank you so much for reading and giving support.(Due to the side of post limited, i will post more pictures on comments!)

author: Chinhdc
author_rank: Contributor
timestamp: December 26, 2021, 03:58:32 pm
content: More pictures about my case with inside PCBI'm looking forwards hearing supports soon.

author: Chinhdc
author_rank: Contributor
timestamp: December 26, 2021, 04:00:25 pm
content: More pictures about my case

author: AVGresponding
author_rank: Super Contributor
timestamp: December 26, 2021, 04:13:20 pm
content: I'm confused; the Fluke 177 has a low battery indicator, so there's no need to perform a test on the battery, the meter will tell you when it's necessary to replace it.Are you saying you measured the battery by removing the battery cover and probing it with the meter while it was powering the meter?

author: Chinhdc
author_rank: Contributor
timestamp: December 26, 2021, 04:20:54 pm
content: To AVGresponding;Yes,i did it, because some other models of Kyoritsu can measure like this.Now, what can i do? Can you help me more?Thank you!

author: AVGresponding
author_rank: Super Contributor
timestamp: December 26, 2021, 04:29:49 pm
content: Without a schematic (I haven't been able to find one) I'd just be guessing.There's a possibility that the battery is too low for proper functioning, if you have a new battery to try in it, that would be the first thing to do.If the battery is good, it would look like the function selection on the ASIC (the brain of the meter) has been damaged; if that is true, the only way to repair it would be to replace the chip.If someone can supply a schematic we'd have a much better chance of making a correct diagnosis.

author: Chinhdc
author_rank: Contributor
timestamp: December 26, 2021, 04:40:42 pm
content: To AVGresponding,I changed another battery, the problem is still.If the problem on the ASIC, it's the worst thing that i cant image.I have asked some technicians, they though there's some malfunctioned or the device maybe shorted circuit inside.So, i hope some one experienced to this problem can help me or give me the fluke 177 schematicsBTW, many thanks to you to give me ideas about this. Have a nice X-Mas seasoning.

author: electr_peter
author_rank: Unknown
timestamp: December 26, 2021, 04:41:43 pm
content: Typical DMMs are not designed to measure their own battery voltage with probes! It can damage the meter. This is why most DMM instructions say to disconnect leads before changing battery. Special internal circuitry is used to show battery status (or use another DMM to measure battery). More info on this topicdmm-reading-it_s-own-battery-voltage-low-voltage-detectionOP measured internal battery with probes, actual damage is possible. Exactly what happens to Fluke 177 I don't know, schematic is needed.

author: Fungus
author_rank: Super Contributor
timestamp: December 26, 2021, 04:46:29 pm
content: Can't you send it to Fluke under warranty?

author: Chinhdc
author_rank: Contributor
timestamp: December 26, 2021, 04:55:43 pm
content: To: electr_peter,So, i would like to receive the schematics, can you send me?thank you.

author: Chinhdc
author_rank: Contributor
timestamp: December 26, 2021, 04:58:37 pm
content: To: Fungus,This case is impossible, it is the used DMM that i have bought. Anyway, with the wrong using, i'm afraid of requiring charge from warranty center. In VN the Fluke service center still unavailable.Thank you.

author: modoran
author_rank: Regular Contributor
timestamp: December 26, 2021, 05:29:12 pm
content: Just buy another meter and thats it.

author: BeBuLamar
author_rank: Super Contributor
timestamp: December 26, 2021, 07:01:02 pm
content: The 177 has a limited lifetime warranty. All you have to do is to call Fluke and tell them the serial number and they would give you an RMA form to send it back. It doesn't matter if you buy it used.

author: electr_peter
author_rank: Unknown
timestamp: December 26, 2021, 07:41:50 pm
content: Quote from: Chinhdc on December 26, 2021, 04:55:43 pmI don't have schematics for 177.

author: e0ne199
author_rank: Regular Contributor
timestamp: December 26, 2021, 10:18:44 pm
content: fluke 177 is on average price so just buy the new one or buy kyoritsu instead

author: AVGresponding
author_rank: Super Contributor
timestamp: December 27, 2021, 12:01:24 am
content: Quote from: BeBuLamar on December 26, 2021, 07:01:02 pmThe coverage this provides varies quite a lot depending on country; still, it won't cost anything to ask them.

author: Chinhdc
author_rank: Contributor
timestamp: December 27, 2021, 01:58:05 am
content: To BeBuLamar,Sorry, but i'm not clear about RMA, can you tell me?Thank you.

author: BeBuLamar
author_rank: Super Contributor
timestamp: December 27, 2021, 03:34:19 am
content: Quote from: Chinhdc on December 27, 2021, 01:58:05 amI am sorry. I thought you are in the USA. You're in Vietnam and I know now. I don't know how the warranty policy in Vietnam. By the way I was born in Vietnam. If you live in the USA and the meter was bought in the USA even if you're not the original owner you can still have Fluke fixes it for free. I have done it many times. I just call them and they would email me an RMA form (RMS stands for Return Material Authorization) then you can send it in with the meter. They only asked for serial number. They didn't aske for the receipt or anything like that.

author: Chinhdc
author_rank: Contributor
timestamp: December 27, 2021, 04:13:13 am
content: To BeBuLamar,It's so great to hear that you were born in VietNam, You are welcomed to visit VietNam. Let me know if you have a chance to go to VietNam, especially to HaNoi.It is the used fluke that i bought, but its original made in USA, with its serialsIn case we have to send it to USA, i think the express fee as the new one price.How can i do?Thank you

author: BeBuLamar
author_rank: Super Contributor
timestamp: December 27, 2021, 06:53:23 pm
content: I think all the 177 are made in the USA but the Fluke may have different policy for meters sold in different countries. There is no service center in Vietnam. If they repair it you will have to send it to Singapore. However, by all mean contact them and see what they say. It doesn't hurt.

author: Fungus
author_rank: Super Contributor
timestamp: December 27, 2021, 07:04:44 pm
content: Quote from: BeBuLamar on December 27, 2021, 06:53:23 pmThere's no need to mention that it's second hand or what happened to it. Model number, serial number, symptoms.If they say "no" then it only cost you an email or phone call.Be sure to let us know how it went.

author: Chinhdc
author_rank: Contributor
timestamp: December 28, 2021, 01:01:07 am
content: Yesterday, the SGP Fluke Center contacted me and quote ~USD200 not include carrier.

author: bdunham7
author_rank: Super Contributor
timestamp: December 28, 2021, 01:55:25 am
content: Without a schematic this might be tough, but I suppose we could do a bit of guessing that it may be similar to other meters that we have schematics for, like the 87V. If it uses the same floating ground configuration where the input ground is 2.5V above the battery negative, shorting the COM lead to the battery negative might blow the 2.5V regulator. The controller would still have it's 5 volts, but anything relying on that ground would not work. The 87V uses an LT1790-2.5, which according to the datasheet is a 6-lead SOT-23 package and may have a marking of "LTPZ". So look for that.Beyond that, you probably need to try and identify as many of the smaller ICs as possible so as to try and reverse engineer it a bit to see where the damage may have been done.

author: dophuc
author_rank: Contributor
timestamp: December 28, 2021, 02:09:07 am
content: In Vietnam, I know there is a company called EMIN that distributes electronic equipment. In addition, they also have calibration and repair services for many types of electronic equipment including Fluke. I think you should try contacting them in this case.https://emin.vn/sua-chua-dong-ho-van-nang-fluke-91342/pr.html

author: AVGresponding
author_rank: Super Contributor
timestamp: December 28, 2021, 02:42:23 pm
content: Quote from: bdunham7 on December 28, 2021, 01:55:25 amDefinitely worth a look, as both the microprocessor and front end ASIC need that -2.5V to function correctly, at least on the 87V, and power rails are easy to check.

author: Chinhdc
author_rank: Contributor
timestamp: December 30, 2021, 03:04:51 pm
content: I found that model 177 has a 6-leads SOT-23 with name LPTZ, follow you guide, i check the pin 6 to COM, it's on a rail; then measure the impendance of pin1 (GND) - Pin4 (Vin) is high ~ 5MOhm; pin 1 - Pin 6 (Vout) ~ 30KOhm (infact the impendance is not stable at a value, it varies). So, it's the sign of defect the LPTZ component?Looking forwards your early tip to bring it back normally.

author: Chinhdc
author_rank: Contributor
timestamp: December 30, 2021, 03:11:18 pm
content: and, i measure in Voltage the LPTZ component (Battery>9VDC):- Pin1-Pin4: 4.92V-Pin1-Pin6:2,475VSo, is any guy have a tip for me about this?

author: bdunham7
author_rank: Super Contributor
timestamp: December 30, 2021, 03:39:24 pm
content: Quote from: Chinhdc on December 30, 2021, 03:11:18 pmIt looks like the power supplies are good. The IC marked 'PCY' right below the LPTZ is your 5.0V regulator, I don't see the 3.3V regulator if there even is one. Look elsewhere for a similar sized IC with the markings 'AQI'. If your power supplies are good, I don't have any other hot tips for troubleshooting this.

author: andyB2022
author_rank: Regular Contributor
timestamp: July 15, 2022, 09:50:02 am
content: Hi, I have the same issue. @Chinhdc did you manage to solve the issue?

author: Chinhdc
author_rank: Contributor
timestamp: July 25, 2022, 02:47:07 pm
content: not yet, the meter is still in the store(

author: Simonv92
author_rank: Newbie
timestamp: July 22, 2025, 09:59:21 pm
content: Quote from: AVGresponding on December 28, 2021, 02:42:23 pmHi, I also have a faulty Fluke 177. Mine doesn't have any sign of life. I've found some corroded traces on the 9V line and repaired them. Now I have 9V on the backlight leds and at the CD4069. But I no power on the upper right part of the pcb at the voltage regulators. Where can I focus my attention? There's probably some other broken track.. my PCB says REV022.Thank you very much!!SimoneP.S. I apologize for reopening this thread but I saw that it contains valuable information that could concern my Fluke...