LG 50PV450-UA no power

[cmslick3]

Hello all,
I'm troubleshooting an LG 50PV450-UA for a coworker of mine, I'm stumped and looking for help.

Original issue: TV shut off, no standby light on front panel, no clicking when plugged in.
To date troubleshooting:
No bulging caps, no obvious heat issues, no destroyed components.

Checked main fuse, GOOD. Checked fuse F302, BLOWN. Replaced fuse F302.
Plugged in TV fuse immediately blows.

Tested D304(SR 104) and R305(0.33 ohm) both blown, Replaced. Diode had to be NTE585 which was the only locally available component. Replaced F302 again.
Plugged in TV fuse blows immediately.

Tested Voltage regulator IC301 and it's completely shorted. Replaced with STR W6053S IC, checked diode and resistor, replaced F302 AGAIN...
Plugged in TV and nothing happens, fuse did not blow, but still no standby light or voltage.

Checked voltage at F302 and it's only reading 100Vdc, should be 160Vdc at standby.

Checked VA and VS, 5V and 17V jumpers and all reading 0.

Checked multiple diodes and resistors across the board, always desoldered, and nothing else seems blown.

At this point I'm leaning towards ordering a new SMPS, but wanted to know where else to check.

Thanks for your help.

[Unspun01]

Re: LG 50PV450-UA no power

I assume you checked all heatsink-mounted components? transistors, diodes, IGBTs, etc?

IC301 likely failed and took out R305 and D304.

I see 3 fuses F801, F101, F302. Are all 3 good?

Check the 3 low resistance white 5W ceramic resistors in case they opened up.

Check the low resistance 2.2ohm resistor? (red red gold gold ?) located near the heatsink by the two large capacitors and fuse F801. I can't make out these markings from a photo I found so I don't know if the resistor or fuse label are accurate.

Can you identify the markings of the multi-pin ICs on bottom of board? I seem to recall one may be a L6599 resonant controller IC (PWM PFC) and it may be damaged also.

https://cdn.badcaps-static.com/pdfs/...7b0cc85afc.pdf

Check for VCC at pin 12, and try to verify other functions against datasheet. Or test for shorts between each pin to ground at the very least.