Mulja tv repair portal

Equipment Repairs => LCD TV forum => Topic started by: Davy on March 04, 2013,12:28:51

Title: Samsung LE32N73BD 4 flashes.
Post by: Davy on March 04, 2013,12:28:51
Have this Samsung LE32N73BD giving 4 flashes repeatedly, looks as though it had all the caps changed..... I discovered that DP804 SMD diode is shorted... anyone know the diode type?

The ident is not readable, would it be a BAV70? This is on the power factor control chip, thanks

Dave
Title: Re: Samsung LE32N73BD 4 flashes.
Post by: jordan on March 04, 2013,13:01:53
-Check capacitor CPB12 (150uF/450V)
-If all the capacitors are OK then replace power IC (F9222L)
-Glue at LM851 on top right-hand side of the board becomes conductive.An un-used hole on PCB allowes the glue to cover SMD zener diode DZM852 on the print side of the PCB.Remove the glue from both sides of the PCB and replace SMD zener diode DZM852 (6,8V)
Title: Re: Samsung LE32N73BD 4 flashes.
Post by: Davy on March 04, 2013,16:41:27
Hi jordan, thanks for the reply.

Well, it wasn't the BAV70 DP804, out of circuit it read OK. Did as you say, removed the inductor and all the brown glue, no damaged to DMZ852 and checks OK at 6.8V on a variable power supply, the gunge blocked the hole but didn't find it's way through.

Changed all the caps inc. the mains block 150uF at 400V, the only thing left as you suggested is try a new chopper chip.

Leaves me wondering if it is an OV trip, there's no shorts as I can see.

Dave

Title: Re: Samsung LE32N73BD 4 flashes.
Post by: jordan on March 05, 2013,11:06:23
How to test F-9222L
Title: Re: Samsung LE32N73BD 4 flashes.
Post by: Davy on March 07, 2013,11:34:40
Hi jordan, you are spot on, changing the F9222L cured the 4 flashes and brought the set back to life... but the set was a scrapper!

There was thin lines on the display, when I took the display out the lines was visible when held against a light, in the same format as though something had damaged the rows of pixels... so I scrapped it, probably 'a supermarket telly', the type of set you 'clod away' when they go faulty, then off to the store for another

I didn't get around to checking the F9222l as per your last post, incidentally I was told I had to order this chip from China... not so, I ordered one from Ohms Supply  in the UK, it was fitted the next day - good service there!

Thank you for your time jordan much appreciated, as you probably know some you win some you lose.

Dave