TC-P50X5, solid red LED, no blinks, no prime, no picture or sound

[johnboy1313]

I picked up a TC-P50X5 a while back with the no power issue common with this PSU. I ordered the IC and replaced it which brought the set to life. I buttoned it up and called it fixed. When I went to sell it, I plugged it in and tried to turn it on. The LED on the front lights solid red and stays lit. The optical audio out on the main board lights for a second, then turns off. Voltage at the main cap starts at ~170 and climbs to ~380, then when the optical audio out light shuts off, it drops back to ~170. If you hold the power button down for three seconds, the LED will turn off and the set is completely unresponsive unless unplugged and plugged back in. I have a second PSU but no other boards to swap out. There is no change with the second PSU installed. There are four wires at connector SN2 on the SN board. There is a S/C between the white wire and the two middle wires at that connector. There are also a few components that show S/C in circuit. I am leaning towards a faulty SN board, but there is no blink code that would suggest it. Do any of you have any ideas?

[dick_barton]

Re: TC-P50X5, solid red LED, no blinks, no prime, no picture or sound

There's a thread with service manual located

https://www.badcaps.net/forum/showthread.php?t=44747

[johnboy1313]

Re: TC-P50X5, solid red LED, no blinks, no prime, no picture or sound

Where are you seeing the service manual in that thread?

[dick_barton]

Re: TC-P50X5, solid red LED, no blinks, no prime, no picture or sound

Look at post #12

[vinceroger69]

Re: TC-P50X5, solid red LED, no blinks, no prime, no picture or sound

this may help?

[johnboy1313]

Re: TC-P50X5, solid red LED, no blinks, no prime, no picture or sound

Look at post #12

I see a datasheet for an IC and schematics for the PSU.

this may help?

Thanks, it's a start, but doesn't really help with the troubleshooting. They reference a training manual. I've had a look at that one and it doesn't really help either. I do appreciate the input though.

[dick_barton]

Re: TC-P50X5, solid red LED, no blinks, no prime, no picture or sound

I see a datasheet for an IC and schematics for the PSU.

The power supply is a good starting point to check what voltages if any are missing.

[johnboy1313]

Re: TC-P50X5, solid red LED, no blinks, no prime, no picture or sound

I've already done that and tried a second power supply.

[dick_barton]

Re: TC-P50X5, solid red LED, no blinks, no prime, no picture or sound

So you have and can confirm that when tested all the voltages are correct ?

[tw2005]

Re: TC-P50X5, solid red LED, no blinks, no prime, no picture or sound

sounds like shorted Vsus. On the SN, Pin 6 or SRV-Vsus to gnd what do you get withe the P2 disconnected.

[tw2005]

Re: TC-P50X5, solid red LED, no blinks, no prime, no picture or sound

I guess you know this but if the PSS is good, a an A-board & SN together is the princely sum of $43 from SJ!

[vinceroger69]

Re: TC-P50X5, solid red LED, no blinks, no prime, no picture or sound

tw2005 is there a training manual that covers this set? ive had a quick google search they list loads of diffrent generations, just for future refrence how do you tell which one covers what models? thanks

[tw2005]

Re: TC-P50X5, solid red LED, no blinks, no prime, no picture or sound

I have not found anything except the 50 UT/ST model. I don't understamd what you mean how do you tell? Year / models/ chassis or look at it.

[tw2005]

Re: TC-P50X5, solid red LED, no blinks, no prime, no picture or sound

at SN2, Pin 1 is gnd, 3,4 are MID or the ERC from the PSS, 6 is Vsus

[vinceroger69]

Re: TC-P50X5, solid red LED, no blinks, no prime, no picture or sound

I have not found anything except the 50 UT/ST model. I don't understamd what you mean how do you tell? Year / models/ chassis or look at it.

Sorry tw2005 i worded that completly wrong (been one of those days) ive just found a site with a fair few panasonic training manuals on i will have a read of them as may help me understand plasmas more and test procedures.