DIYbanter - sceptre x425bv tv main board smoked Q7

On Wednesday, November 25, 2020 at 3:40:01 PM UTC-5, Stu jaxon wrote:
Hi Group, can someone help please,.? I put the LVDS wiring harness on wrong in the main board #T. RSC8.10B 12305.. B12083477,. and smoked Q7, I know it's a transistor, can someone tell me a part number or suggest a replacement???

I'm sure you're aware there are no schematics anywhere on those mains.

There's a high probability that that transistor is the 12V switch used to power up the TCON on command. Remove what's left of the transistor, and see if either the collector or emitter of that transistor rings out at zero ohms to the paralleled red wires of the LVDS harness. There are typically 4, 6, or 8 wires grouped at one end of the harness that provides the 12V. If that group connects to that transistor, it's probably just a switch.

If so, plug in the TV with the transistor removed and take some voltage readings. If you see 12V appear at the E or C when you power up, take a reading on the base. Your base reading will determine whether to use an npn or pnp.

Alternatively, you can just jump out the E and C and call it a day. Those mains were used in low end toilets like Elements, Sceptres, Insignias, etc. If your lucky, nothing else beside the switch will have been damaged.