DP42849 Wont stay powered on.

[dxhac69]

I have a DP42849-04 that i have been working on. I have replaced the main board due to a surge.
i have my 5v, 3v, 24v, and 12V when powered on. i have 3v and 5v when not on. When i turn the TV on, the green light comes on and then it powers back off about 10 seconds later. I can do this 3 times then the tv goes into protect and i have to unplug it for a moment to reset it.

Any help would be appreciated.

[budm]

Re: DP42849 Wont stay powered on.

You can start with this:
https://www.badcaps.net/forum/showthread.php?t=39740

[dxhac69]

Re: DP42849 Wont stay powered on.

It is a N7AE but the tuner says N7AH so that is what i installed in it to match the original.


Ignore the lg one it is for a different tv i am working on

[budm]

Re: DP42849 Wont stay powered on.

So do see the backlights come on too?
If not, remove the connector K8L on the main board to see if the backlights will come on.
So far it looks like the main board is sending the PS-ON to turn on the rest of the power supplies OK.
BTW, there are many thread about this model:
https://www.badcaps.net/forum/search...archid=6468288

Also read this:
https://www.badcaps.net/forum/showth...=sanyo+DP42849

[dxhac69]

Re: DP42849 Wont stay powered on.

i unplugged that connector. i do not get a back-light with or with out it unplugged. i have tried the forum search but i cannot find much on this particular chassis or with a problem that is a lot closer to mine.

[budm]

Re: DP42849 Wont stay powered on.

Well you do have at least the inverter problem because the backlights should be on.
https://www.badcaps.net/forum/showth...&highlight=K8L
And may be the main board problem too:
http://www.coppelltvrepair.com/p/44/...repair-service

We need pictures of your inverter board/s.

[dxhac69]

Re: DP42849 Wont stay powered on.

Here is the inverter board and the tcon while i am there

[budm]

Re: DP42849 Wont stay powered on.

So the fuse F1 is good and it has 24VDC at both ends with ref to the chassis GND?
dcv at TP5~8?
LG 6632L-0520A (2300KTG012A-F, PNEL-T805A) Backlight Inverter
http://www.shopjimmy.com/lg-6632l-05...-inverter.htm#

[budm]

Re: DP42849 Wont stay powered on.

Some info I found on line.

[dxhac69]

Re: DP42849 Wont stay powered on.

i get .5 vdc at tp5~8. i get 24vdc at the fuse.

[dxhac69]

Re: DP42849 Wont stay powered on.

The service manual is for a -00 chassis. I checked the chip and it is not one listed as having the on-off problem. This one turns on for 10 seconds and shuts down. It wont turn back on again until you press the power button. It will not turn back on after the third time.

[budm]

Re: DP42849 Wont stay powered on.

i get .5 vdc at tp5~8. i get 24vdc at the fuse.

Is this with K8L connector back in place?

[dxhac69]

Re: DP42849 Wont stay powered on.

Yes, I have all the connectors hooked back up

[budm]

Re: DP42849 Wont stay powered on.

That means the main board is not sending any command signal to the inverter at all.
Put the red probe on pin 5 og the K8L connector and take the DCV reading when the TV is OFF and when the power switch is activated to see if there is any action on that pin.
Also check pin 1 to see if you have 5VDC.
It looks to me you may have problem with your 'NEW' board.

[dxhac69]

Re: DP42849 Wont stay powered on.

I checked at pin 1 and I do not have 5vdc with it off or when it is power cycled on K8L.

[budm]

Re: DP42849 Wont stay powered on.

That 5V has to be there when the TV is on, since I do not have the exact diagram for the main board, we will have to figure out if that 5V is switched or it is from standby power supply, more research has to be done for this 04 chassis.
You may want to contact coppell.

[dxhac69]

Re: DP42849 Wont stay powered on.

I traced the path on pin 5 on the K8L connector and it dives in under the broadcom processor.