Sanyo 42" No Startup

[Loose-Cannon]

Hey guys.... Glad to be here and hopefully learn a thing or two.

I have a 2011 made Sanyo model DP42841-00 that I believe took a surge through the antenna coax. (we only use antenna) and I would like to narrow down the circuit board that is most likely not working correctly. The set does absolutely nothing... no standby... nothing. I have the TVs back panel removed, and have inspected all the boards (both sides) for damage and can NOT for the life of me see anything apparently obvious wrong.

Reading here, I just jumped the +5v (5v IS present) and PS-ON pins coming off the power supply with the harness removed and checked the 24v and 12v pins. All pins labeled 24v are only showing 10.4v and all 12v pins are showing only 4.8v. Obviously nothing on those pins when +5v/PS-On is not jumped.

Based on this, is it safe to assume the power supply board is fubared?
Any other fairly simple things I can check?
Is it possible for the surge to go through the analog board via the coax and toast the power supply but not effect the analog or main boards?

This power supply does not appear to have a fuse.... not that I can find anyhow.

Any help narrowing this down better would greatly be appreciated!

[jihadi_john1]

Re: Sanyo 42" No Startup

Can we get some pictures of both sides of the power supply board?

[Loose-Cannon]

Re: Sanyo 42" No Startup

Can we get some pictures of both sides of the power supply board?

No problem...

[Hamie]

Re: Sanyo 42" No Startup

If you have 5v and no standby light then you also have a faulty mainboard or problem with The IR sensor.

[Loose-Cannon]

Re: Sanyo 42" No Startup

What if....

I replace the main board, power supply board, and the analog board? lol

I dunno... from my reading on this thread regarding the same model just a 46", the set wont even have the standby light if the PS dont put out the proper 12 and 24v. ?? https://www.badcaps.net/forum/showthread.php?t=40435

[Hamie]

Re: Sanyo 42" No Startup

No point buying things you don't need.
Btw did you also jump BL-ON or INV-on to 5v

If you jump ps-on to 5v and also 5v to bl-on the backlight should come on. If you get backlight then I'd suggest changing out only the mainboard.

[Loose-Cannon]

Re: Sanyo 42" No Startup

did you also jump BL-ON or INV-on to 5v

I do not see those on the power supply board.... where are they?

With the main board disconnected... should I not have 12 and 24v after jumping the 5v and PS-ON ??

[Loose-Cannon]

Re: Sanyo 42" No Startup

This is what I have coming off the power supply board going to the analog and main boards.

[Loose-Cannon]

Re: Sanyo 42" No Startup

I did however just find that the analog board must have gotten hot because these plastic tabs on the under side look cooked, and the vertical metal parts on the tip side look cooked also. Not sure if this would have cooked the main board thats attached to it. There wasnt anything other then the antenna connected to this board at the time it went out.... no audio cables etc.

[Hamie]

Re: Sanyo 42" No Startup

Just skimmed the first post.
All 12 and 24 rails should come up with jumper in place.
However still doesn't explain why no standby.
I trust that you have everything disconnected from the PSB when you have ps-on jumper in place?

[Loose-Cannon]

Re: Sanyo 42" No Startup

Just skimmed the first post.
All 12 and 24 rails should come up with jumper in place.
However still doesn't explain why no standby.
I trust that you have everything disconnected from the PSB when you have ps-on jumper in place?

Actually my en-laws TV, so Im not even sure this model has a standby light.

I just tested again.... Only thing connected to the board was the power cord. ps-on and +5v jumped together I only have 10.4v on the ones that say 24v, and only 4.8v on the ones that say 12v.

[dick_barton]

Re: Sanyo 42" No Startup

If you have 5VSTB can you connect PS_ON to 5VSTB using a 1K resistor and measure the dc voltage across D604. Also measure the DC voltage between Pin 2 & Pin 4 of IC602 taking care not to short anything as this is on the hot voltage side.
Test with main board disconnected.

[Loose-Cannon]

Re: Sanyo 42" No Startup

If you have 5VSTB can you connect PS_ON to 5VSTB using a 1K resistor and measure the dc voltage across D604. Also measure the DC voltage between Pin 2 & Pin 4 of IC602 taking care not to short anything as this is on the hot voltage side.
Test with main board disconnected.

No, sorry. Im afraid thats a bit out of my capabilities and I already but the set back together. Maybe Ill get a PS and main boards and see what that does.