Samsung TV Model HV32HD_9DY - Page 1
Forum section: electronics / repair

author: DarkZero
author_rank: Regular Contributor
timestamp: May 15, 2015, 11:37:47 am
content: Hello All!i measured voltages and switched all the caps, tv just turns on for a brief moment then off any suggestions?

author: Srbel
author_rank: Frequent Contributor
timestamp: May 15, 2015, 11:54:55 am
content: Capacitors should not stand like that on their leads. You should push them completely to the PCB and then solder the leads.

author: wraper
author_rank: Unknown
timestamp: May 15, 2015, 11:57:10 am
content: Measure resistance of the secondary windings (two per each transformer) on both CCFL inverter transformers. All of them must be equal in resistance. Otherwise transformer is faulty.

author: wraper
author_rank: Unknown
timestamp: May 15, 2015, 12:05:15 pm
content: Also, it seems that you have used Samwha RD series capacitors. They are unsuitable for repair of such PSUs unless for replacing some capacitors which originally were of general purpose series. All other must be replaced with LOW ESR series. General purpose capacitors will work for some time but will fail soon.

author: DarkZero
author_rank: Regular Contributor
timestamp: May 15, 2015, 12:51:04 pm
content: hello!Im not planing to leave these capacitors it is just for try outs. i did check transformers all 4 secondaries reads 1k. is there anyway to know 100% if its the inverter part of the board the one that fails?

author: wraper
author_rank: Unknown
timestamp: May 15, 2015, 02:30:01 pm
content: Does it switch off completely or only display backlight disappears? Backlight disappearing could look as TV switches off but actually is not.

author: DarkZero
author_rank: Regular Contributor
timestamp: May 15, 2015, 05:16:44 pm
content: when it turns on backlight, pin that says inverter on/off stays at 5v so my guess is that it is turning off only backlight not the whole tv. that 5v goes to the 16pin chip which in my opinion is some kind of oscillator for the mosfets but i cant see markings on it.

author: wraper
author_rank: Unknown
timestamp: May 16, 2015, 12:55:49 pm
content: Then it could be one of the CCFL tubes being faulty and causing protection to shut down the backlight. Could be some fault in the inverter too, like faulty mosfet, high voltage (blue) capacitor or something else. But in most cases it is faulty transformer (already checked) or CCFL.

author: Rasz
author_rank: Super Contributor
timestamp: May 18, 2015, 08:17:08 am
content: like wraper said can be one of the lampsyou can check lamps individually by substituting one by one with a working one (from broken panel), or by trying to power your lamps from another inverter

author: vladko
author_rank: Newbie
timestamp: May 03, 2022, 07:36:40 am
content: Hello, my tv stopped - no standby no nothing so i suspect power supply board. I have some knoweledge in electronics but i am an amateur in tv repairs can you advise me how to check the board and where is the problem. Thank you

author: vladko
author_rank: Newbie
timestamp: June 02, 2022, 10:27:15 am
content: hello again, i have changed all electrolite capacitor on board and now turns on but for few seconds and off again. then automaticly starts on again for few seconds and turns off again. Screen lights on, no signal sign and turns off. Any idea where is the problem ? Thank you

author: PKTKS
author_rank: Super Contributor
timestamp: June 02, 2022, 01:05:11 pm
content: Quote from: vladko on June 02, 2022, 10:27:15 amPOKING around will not help.. and will cost you...May be even more than paying a decent repair shop...YOU DO NEED a lot of skills to do this kind of job..It may seem easy... i assure you .. it is not.A lot can go wrongPaul

author: vladko
author_rank: Newbie
timestamp: June 02, 2022, 01:53:53 pm
content: the TV is already in the trash... if I fix it will make me happy but if burns out not a big deal ... i just want to try ... not gonna open TV repair service and thats why i am looking for advice from more skilled people ... if it works ... Thank you

author: PKTKS
author_rank: Super Contributor
timestamp: June 02, 2022, 02:16:15 pm
content: so.. if you do not care how much spending..You will need a good quality tester likehttps://www.aliexpress.com/item/4001155350991.htmlseveral other models also available - this is plain standard.Basic faults on PANELS are LED lamps and/or input mosfets..Rare cases you have bad caps. they are high quality. Made to last.Input is over stressed by LAMP panels and heat backside ..booster diodes and fault gates also fail.You need a schema . just google around best close matchPoking the primary side of SMPS panels is DANGEROUSYou need a proper understanding.Paul

author: vladko
author_rank: Newbie
timestamp: June 03, 2022, 05:57:43 am
content: if there was a problem with backlight wouldnt be powering off just the backlight and the tv still work ? i have change leds on backlight on another tv but the tv was working ( there was sound for tv show etc. )this tv is powering off afte few seconds - the whole tv - no power on led, no nothing.I am sorry for my bad english. Will check the backlight as you advise me. Thank you.Should I remove mosfets from board before testing it ? If I understand it right mine are 4506GEH

author: PKTKS
author_rank: Super Contributor
timestamp: June 03, 2022, 02:44:19 pm
content: If just a SINGLE LED LAMP is failing it will trip the protection.The symptom is like a blinking front panel led on/off..The same happens when other faults trip protections..bottom line... if you can not understand the circuit you will not find the fault..These PANELS have a lot of protection built in.. and a single led WILL TRIP protection and shut down the whole system.Paul

author: vladko
author_rank: Newbie
timestamp: June 06, 2022, 07:37:28 am
content: i have never opened tv with lamps before, just with led strips. There just the backlight wont lid but the tv is working. I guess with lamps is as you say. I ordered the tester you recomend but dont know when will be here ( I hope to be less then a month ) Will check lamps first then will poke around other stuffThank you

author: PKTKS
author_rank: Super Contributor
timestamp: June 06, 2022, 11:32:19 am
content: My friend... today.. two terms are messed up- TVs (aka they are CRTs.) are blended with FLAT PANELS- LAMPS.. are blended with LED stripes..As there are only PLASMA and CCFL alternatives...If you plan to enter this arena... get yourself good videos on how to open panels...and tools to do the job... (open kits...)You need to understand how the modern LED drivers are self protectedAnd how the main PSU is interlinked with the rest...It is not trivial.Paul

author: vladko
author_rank: Newbie
timestamp: July 13, 2022, 11:50:16 am
content: my ordered led tester came but as i said the tv is with ccfl lamps. Is there a way to test the lapms or i need cclf tester too ?

author: vladko
author_rank: Newbie
timestamp: July 18, 2022, 10:32:25 am
content: well after few test and measurements it turns out that all ccfl are working - checked with inverter from 17" monitor. All lamps started with 1,90 mA and settle at 1,5 mA. I dont know how many amps must be but i guess the lamps are at the end of their life and the inverter protection is triggered. IS there a way to fool the inverter and squeeze the remaining life of the lamps ? Saw a few methods with resistors but to lower the current ...Thank you

author: PKTKS
author_rank: Super Contributor
timestamp: July 18, 2022, 01:40:45 pm
content: Quote from: vladko on July 13, 2022, 11:50:16 amhttps://www.aliexpress.com/item/1005003193526900.html