Sanyo DP42849 - Power Supply Issues DPS-260LP

[wcsd106]

I picked up a cheap Sanyo LCD TV from Craigslist this week. It is a model DP42849.

The TV will not power on and no standby LED is visible.

With the power supply board pulled, I am not getting the 5v standby voltage at the multi pin connector.

A voltage reading across the large 150uf/450v electrolytic capacitor on the primary side, shows that I am only getting 170v.

The power supply board is a DPS-260LP.

Seems like my problem is more than likely on my primary side.

Any ideas?

[wcsd106]

Re: Sanyo DP42849 - Power Supply Issues DPS-260LP

Pictures component/trace side of power supply board.

[CapLeaker]

Re: Sanyo DP42849 - Power Supply Issues DPS-260LP

yep. force the psu on without the main board and see if all voltage rails come up

[wcsd106]

Re: Sanyo DP42849 - Power Supply Issues DPS-260LP

I have tested with the 5vsb pin shorted to the PS_ON pin. Still nothing. With or without the pins connected, I do not have the 5v that should be on the standby pin even when the PSU is off.

[CapLeaker]

Re: Sanyo DP42849 - Power Supply Issues DPS-260LP

so nothing at all on any of the pins? Be careful working on the primary side as there are lethal voltages. Check how much voltage you get on the main filter cap.

[wcsd106]

Re: Sanyo DP42849 - Power Supply Issues DPS-260LP

That's correct. Nothing at all on any of the pins.

At the main filter cap, I am seeing approximately 170v.

[CapLeaker]

Re: Sanyo DP42849 - Power Supply Issues DPS-260LP

trace the stby voltage rail from the pin back to the secondary of the transformer. Check cap and diode. if that's all good, you have to check things on the primary side. So be very careful there. Kind of need to find a schematic, or you have to trace it.
Look at D951 something drew a lot of current and it got hot.

[Chevyman204]

Re: Sanyo DP42849 - Power Supply Issues DPS-260LP

Don't mean to jump in but I think i have a ps problem as well. The ps board is the same as pictured above. My bl-on only has 2.4v I think it is suppose to have 3.3v. I can see picture after powered on for one second then it goes black, sound is good. I just so happen to have a second main board from another set that I tried to see if the main board was preventing the bl-on voltage to be low. There was minimal change in voltage. Gained .1v with second board.

Not sure what to do next, would the bl-on voltage being low by 1 volt prevent the back lights from turning on?

If I'm not following forum procedure please let me know cause I can start another post.

I wish the other tv that works had the same ps board so I could just switch it to verify lights. I think the inverter boards are separate on the other set but the main boards are the same.

[jjaypops]

Re: Sanyo DP42849 - Power Supply Issues DPS-260LP

Ever find out what was wrong chevyman204? I am having the same issue. Thanks

[ladywinn256]

Re: Sanyo DP42849 - Power Supply Issues DPS-260LP

I picked up a cheap Sanyo LCD TV from Craigslist this week. It is a model DP42849.

The TV will not power on and no standby LED is visible.

With the power supply board pulled, I am not getting the 5v standby voltage at the multi pin connector.

A voltage reading across the large 150uf/450v electrolytic capacitor on the primary side, shows that I am only getting 170v.

The power supply board is a DPS-260LP.

Seems like my problem is more than likely on my primary side.

Any ideas?

[ladywinn256]

Re: Sanyo DP42849 - Power Supply Issues DPS-260LP

Wondering if anyone has found or had this problem power supply board burns resistor R1 and R2 ???

[budm]

Re: Sanyo DP42849 - Power Supply Issues DPS-260LP

http://www.shopjimmy.com/catalogsear...t/?q=DPS-260LP
LP or LPB?
R1 and R2 are the through hole 10M Ohms resistors as I can see in the pictures, is that right?
What is the board not doing?