Burnt out resistor and capacitor TV PSU

Thread Starter

Rob.s

Joined Jun 8, 2019
4
I have an old TV (Philips 32PFL3807T/12 3800 series with 715G5194-P01 PSU) that will not power on so thought would be interesting to attempt a repair.

It was easy to spot the burnt out capacitor (C9312) and resistor (R9302) which I am planning to replace but wondering if I should look for something else as I assume resistors don't just burn out? According to the attached schematic these are part of the standby circuit.
 

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Dodgydave

Joined Jun 22, 2012
10,139
Check IC9301 for shorted pins 7 , 3. This is the chopper ic for the Switchmode psu.

Also check D9304 and ZD9315 for shorted.
 

Thread Starter

Rob.s

Joined Jun 8, 2019
4
Thanks for the replies. I will check those components and fingers crossed it's just the capacitor the killed the resistor.

Is this some kind of special resistor that's blown? Been trying to find something similar looking online.
 

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SLK001

Joined Nov 29, 2011
1,548
Thanks for the replies. I will check those components and fingers crossed it's just the capacitor the killed the resistor.

Is this some kind of special resistor that's blown? Been trying to find something similar looking online.
It acts as just a fuse. The capacitor looks like it suffered a dielectric breakdown failure. If it did, the resistor blew to protect the rest of the circuit. Replace the cap and short out the resistor to check for functionality. If that fixes the PS, just replace the short with the proper resistor.
 

Thread Starter

Rob.s

Joined Jun 8, 2019
4
Thanks to all for the advice. I replaced the cap and resistor and the TV is working again! :)

Couldn't find a similar resistor anywhere - just someone on another forum trying to ID the same component so I have replaced it with a carbon film one rated at 2w. I am guessing the fused resistor is mainly to protect other components rather than safety as there are fuses elsewhere on the board.
 
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