Samsung LN52A650A1F - Shorted components PSU: Fix or replace?

[caphair]

Found the two mains fuses blown, traced to shorted bridge rectifier as well as some mosefts and diodes. Varistors seem fine as don't measure shorted. However I've been reading shorts on random diodes (in circuit) on secondary side, one diode in parallel with relay measures .040v in both directions is that measuring the relay coil resistance?

Would you replace these or just replace entire board? Friend said he plugged tv into a two prong outlet and then heard a pop after it was on. I'm wondering if bypassing the ground prong caused this or not?

[Andrew F. Ali]

Re: Samsung LN52A650A1F - Shorted components PSU: Fix or replace?

Replace.....is my choice.

[ReeceyBurger123]

Re: Samsung LN52A650A1F - Shorted components PSU: Fix or replace?

In my opinion if you know how to repair it do it buying a replacement might not be as reliable I found this out the hard way, when a used Psu failed with in months so I repaired it by replacing the parts that failed and been working for over a year now.

[CapLeaker]

Re: Samsung LN52A650A1F - Shorted components PSU: Fix or replace?

Depends what the cost of a new PSU and availability is. I mean if you can get a new one for 50$, I'd be replacing this sucker. Unless you want to fix it anyway for educational purpose.

[caphair]

Re: Samsung LN52A650A1F - Shorted components PSU: Fix or replace?

Found one for $60 on eBay. Also noticed shop Jimmy sells a repair kit for the power mosfets/diodes/fuses that typically go bad in these models for $20 but with shipping comes out to $30.

I'd like to replace myself for educational purposes but worry I may have missed some shorter smd in correspondence or something.

[caphair]

Re: Samsung LN52A650A1F - Shorted components PSU: Fix or replace?

I was wondering how do you determine if similar PSU are compatible with model tvs? One I found looks very similar but model numbers slightly off.

It's listed as a LN52A540P2F

[CapLeaker]

Re: Samsung LN52A650A1F - Shorted components PSU: Fix or replace?

usually SJ tells you that if one PSU from a different TV is a alternate part for yours. Other than that, you would have to do all the work yourself by comparing the mounting, the pin outs, ratings, etc.

[budm]

Re: Samsung LN52A650A1F - Shorted components PSU: Fix or replace?

What is the P/N on the board?
BN44-??????

[budm]

Re: Samsung LN52A650A1F - Shorted components PSU: Fix or replace?

http://www.shopjimmy.com/samsung-bn4...wer-supply.htm

??

[dick_barton]

Re: Samsung LN52A650A1F - Shorted components PSU: Fix or replace?

A fault in the secondary has probably taken down the components in the primary. You seem to have found most of the faults. To check the diode in parallel with the relay you need to lift one end of the diode otherwise you are reading the relay coil resistance.
A home repair I would have though would be worth while.

[budm]

Re: Samsung LN52A650A1F - Shorted components PSU: Fix or replace?

BTW, the LEDs in that video is the dual-LED (two LEDS connected in series into one package).

[budm]

Re: Samsung LN52A650A1F - Shorted components PSU: Fix or replace?

Oops, please disregard my post 11, wrong thread.