Sanyo CE37LD81-B Stuck in standby

[badcaphunter]

I have a sanyo CE37LD81-B, it has a 17PW20 v2 power supply and 17MB22-2 main board, i originally suspected a bad PSU so ordered a replacement but this didn't solve the issue. When powered on the voltages drop steadily but when i remove connector PL803 from the PSU (this goes to the mainbopard) the voltages remain steady.

All i get is a blue standby light

[ReeceyBurger123]

Re: Sanyo CE37LD81-B Stuck in standby

Ahh Vestel junk, probably corrupt epprom. Luckily on these sets the epprom is an 8pin socketed Ic so you can just swap it for another one. Do you know what it looks like ?

[badcaphunter]

Re: Sanyo CE37LD81-B Stuck in standby

Hi Reecey, Thanks for the quick reply.

I have ordered a few so will try that as soon as they arrive.

[badcaphunter]

Re: Sanyo CE37LD81-B Stuck in standby

I managed to find these if it helps

[ReeceyBurger123]

Re: Sanyo CE37LD81-B Stuck in standby

Cool cheers, keep us updated

[badcaphunter]

Re: Sanyo CE37LD81-B Stuck in standby

ok so i got the epprom's and powered on still solid standby light, no flashes.
I think the mainboard is going into protection mode, i will test the voltage regulators on the mainboard when i have time.

I thought it was a PSU issue, i ordered a used PSU of ebay. i tested both PSU's out of the TV and they tested ok
When i removed PL803 and powered on the 24v rail was steady but when PL803 is connected i get 24v for a second then it diminishes down to 0v.

I'm thinking of buying a mainboard but i would rather try fix this one.

I have no info on the history of this TV set as it came as a bundle of TV's.

[badcaphunter]

Re: Sanyo CE37LD81-B Stuck in standby

PL803
pin
1. 0v 0.01 then 1back to 0v
2. 0v jumps to 1.3v then back too 0v
3. 0v 0v
4. 0v 0v. this is a yellow wire and shorted to ground
5. 0.5v jumps to 2.5v then back to 0.06v
6. 0.4v 1.75v
7. 0v 0v
8. 0v jumps to 11v then down to 0v
9. ground
10. ground

PL602 measure all good

PL403 buttons measure all good

this is the mainboard

PL002

1. 0.65v - 5v
2. 0.51v - 3.36v
3. 0.51v - 3.36v
4. G
5. G
6. G
7. G
8. 0.51v - 3.35 drops to 0.2v
9. 0.52v - 3.35 drops to 0.18v
10. 0.52 - 3.35 drops to 0.17
11. 0v - jumps to 4v then drops to 0v
12. 0v - jumps to 4v then drops to 0v

When i disconnect PL003 from the mainboard the 3.3v pins on PL002 dont drop.

I took some resistance measurements with power disconnected

PL802

1. 1.04k
2. 1.04k
3. 1.04k
4. 1.04k
5. 1.04k

PL813

1.G
2 G
3. 7.1k
4. 7.1k


Thanks for the help guys i am trying to learn electronics myself, read a few books and read a lot of posts on here.

[badcaphunter]

Re: Sanyo CE37LD81-B Stuck in standby

this diode i pointed out measures 550 one way and 158 other way. pin 4 on PL003 is grounded, the wire is yellow so not sure if that's right?. i do believe the problem is with this board.

[ReeceyBurger123]

Re: Sanyo CE37LD81-B Stuck in standby

Yes it would seem the main board is the issue. Tom66 had a thread about this board dead will try find it.

[badcaphunter]

Re: Sanyo CE37LD81-B Stuck in standby

Ok so i pulled pin 6 of PL803 down on the PSU to force the PSU on and felt over the mainboard with the back of my hand, IC100 was getting really hot, when i put my finger on it i had to pull off after 4-5 seconds as it was so hot, this is a drx3960a chip. not sure where to go from here.

[ReeceyBurger123]

Re: Sanyo CE37LD81-B Stuck in standby

Got an image of the chip buddy ?

[badcaphunter]

Re: Sanyo CE37LD81-B Stuck in standby

i dont have air station and i doubt i can do i with an iron without damaging the pads.

[badcaphunter]

Re: Sanyo CE37LD81-B Stuck in standby

I think i'm going to buy a 17pw22 board, even if the boards dont match exactly i can use to IC100 as they match, my mate is good with his hot air station. i can get one for £6.40 all in on ebay so i wont be losing much if it does not work and i can use it for other donor parts if anything else has gone along with this chip.

http://www.ebay.co.uk/itm/MAIN-AV-BO...cAAOSwoudW8V1D

[badcaphunter]

Re: Sanyo CE37LD81-B Stuck in standby

ok so i've put this on the back burner for a while, i'll keep you posted as to where this goes.
once again thanks for the help ReeceyBurger123