LG 60pv400 gets faint image on screen for 2 seconds

[woodman45]

This LG 60pv400 red light comes on after plugging in.when you turn power button on red light goes away then faint snow image comes on for 2 seconds then goes out.press power button as in to turn off red light will remain.
I did confirm on power supply test points vs=200 va=54
I followed from ps to both y and z boards and they both are matching voltages from ps.
I did tested all capacitors on video board all read good with no shorts except c809 and c810.
My question is if I replace those should that resolve the problem or is there something else I need to look at?
Thanks in advance.

[tvtimmy]

Re: LG 60pv400 gets faint image on screen for 2 seconds

Have you read all the threads here on this model? Search the model number and you will get a ton of clues what to do. Pattern tests, cracked solder joints, blown IBGTs on zsus and ysus boards, and don't power the tv on with screws missing. Do a little research. It will steer you in the right direction.

[woodman45]

Re: LG 60pv400 gets faint image on screen for 2 seconds

Have you read all the threads here on this model? Search the model number and you will get a ton of clues what to do. Pattern tests, cracked solder joints, blown IBGTs on zsus and ysus boards, and don't power the tv on with screws missing. Do a little research. It will steer you in the right direction.

Yes I've been going through all the threads here and the trouble I'm having is identifying which are the test points. I've never done a jumpered test pattern.

[tvtimmy]

Re: LG 60pv400 gets faint image on screen for 2 seconds

Unplug the power cord. Un-latch the ribbon circled in black. Put a paper clip in both the holes circled in red. Plug the tv back in and look for the test patterns on the screen.

[tvtimmy]

Re: LG 60pv400 gets faint image on screen for 2 seconds

Forgot to post the picture.

[woodman45]

Re: LG 60pv400 gets faint image on screen for 2 seconds

Unplug the power cord. Un-latch the ribbon circled in black. Put a paper clip in both the holes circled in red. Plug the tv back in and look for the test patterns on the screen.

Thanks tvtimmy, I ran the jumper and unplugged cable plugged tv in no test pattern showed just the faint image for 2 seconds and disappeared.

[woodman45]

Re: LG 60pv400 gets faint image on screen for 2 seconds

I starting checking fuses and fs103 on zsus board is blown.I looked at inductor solder joints and there was cracks so i reflowed solder on them.
I'm guessing the next step is to test igbt's and other components.I will research other threads and get back.
I took ysus board off and noticed cracks in the inductor solder joints,I'll re-flow them later tonight or tomorrow.

[tvtimmy]

Re: LG 60pv400 gets faint image on screen for 2 seconds

Always remember to put ALL THE SCREWS back in the zsus and ysus boards before plugging the tv back in.

[woodman45]

Re: LG 60pv400 gets faint image on screen for 2 seconds

Always remember to put ALL THE SCREWS back in the zsus and ysus boards before plugging the tv back in.

Yes I've read how important that is for the boards to be properly grounded.I appreciate all your help tvtimmy.

[tvtimmy]

Re: LG 60pv400 gets faint image on screen for 2 seconds

No problem, let's get 'er fixed. When you find the bad ibgts, I have a method of getting them out. Involves some snipping of the heatsinks.

[tvtimmy]

Re: LG 60pv400 gets faint image on screen for 2 seconds

There are smaller fuses on the y and z boards too.

[woodman45]

Re: LG 60pv400 gets faint image on screen for 2 seconds

Do the igbt’s have to be out of circuit to test? And do I test them in continuity mode?

[tvtimmy]

Re: LG 60pv400 gets faint image on screen for 2 seconds

You can test them in the board. Yes , test them in continuity mode. Any combination of beeps is bad. The diodes will beep too because the ibgts are shorted and in the same circuit. Test the parts marked with a "Q".

[woodman45]

Re: LG 60pv400 gets faint image on screen for 2 seconds

You can test them in the board. Yes , test them in continuity mode. Any combination of beeps is bad. The diodes will beep too because the ibgts are shorted and in the same circuit. Test the parts marked with a "Q".

Ok I tested all the Q ones and most of them are bad.beeping away.i pulled the y board no beeps on them.
If I get a repair kit should it include all the igbt's or do you have any recommendations?
Also the fuse that you posted a pic of is showing good.

[woodman45]

Re: LG 60pv400 gets faint image on screen for 2 seconds

Q201.202.203.204,205,206,207 no shorts. Q208,209,210,211,212,213 shorted.

[tvtimmy]

Re: LG 60pv400 gets faint image on screen for 2 seconds

I've ordered parts from this guy before, always good stuff from him. Look up your board number and search for it on Ebay.

[woodman45]

Re: LG 60pv400 gets faint image on screen for 2 seconds

I found this on eBay for $20 so I'm gonna have to desolder and pull the heat sinks completely out right?

[tvtimmy]

Re: LG 60pv400 gets faint image on screen for 2 seconds

I've only had the bad ibgt's on the 2 that I repaired. No bad resistors. You have to be very good at soldering to change out the IC driver chips.I took a tin snips and cut the overhang of the heatsink above the bad parts and bent them up so I could get to the screws. I think I removed some capacitors that were in the way too. I bent the cuts back down when replaced.

[woodman45]

Re: LG 60pv400 gets faint image on screen for 2 seconds

I've only had the bad ibgt's on the 2 that I repaired. No bad resistors. You have to be very good at soldering to change out the IC driver chips.I took a tin snips and cut the overhang of the heatsink above the bad parts and bent them up so I could get to the screws. I think I removed some capacitors that were in the way too. I bent the cuts back down when replaced.

I found the ibgt's from the guy you got em from.I'm gonna get them.Man i appreciate all your help and tips. I'll get back when i get them and start working on it.

[ajshoe]

Re: LG 60pv400 gets faint image on screen for 2 seconds

I've ordered parts from this guy before, always good stuff from him. Look up your board number and search for it on Ebay.

I've used this guy before also - not competent. sent him 3 power boards to repair and he shipped them back like an 8 year old would. boards came back all broke. I'll never use or trust him again. Had to agree with fleabay so unfortunately I couldn't give him negative feedback. just my 2 cents worth