Panasonic TV turns on, displays then turns off.

[Techie012]

Hi all,
I recently aquired a Panasonic TH-60CX700Z.
When plugged in it turns on, displays the text "HDMI 16:9" and then mediately shuts off and I can hear the relay cut out.
I have replaced all the caps on the cold side of the power board with no luck, none of the caps appear to be damaged or swollen, I have tried disconnecting everything but the main board and the problem still persists so I believe the problem is with the power board, however I don't know what components to check/replace.

Any help is appreciated.
Thanks.

 

[Delta Prime]

Have you tried looking for the service manual?

Service Manual finder | Elektrotanya

Find service and user manuals | Elektrotanya | 2025/09/25

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That’s only one example,it seems you know how to solder, desolder
it is inferred that you know something about electronic theory or once you found this serves manual. You wouldn’t know how to follow the instructions and we can help you on that if you’d like..

 

[Techie012]

Thanks for your response.
Yes, I cannot find an exact match but this service manual appears to have the same power board at least.

Elektrotanya for electronics experts

Electronics forum for electronics experts to repair defective appliance.

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[Techie012]

Have you tried looking for the service manual?

Service Manual finder | Elektrotanya

Find service and user manuals | Elektrotanya | 2025/09/25

elektrotanya.com

That’s only one example,it seems you know how to solder, desolder
it is inferred that you know something about electronic theory or once you found this serves manual. You wouldn’t know how to follow the instructions and we can help you on that if you’d like..

If you could walk me through what components I should check that would be great, initially I thought it might be one of the capacitors driving the relay hence why it keeps cutting out but they look fine so I am not sure how to proceed.

 

[Delta Prime]

I have replaced all the caps on the cold side of the power board with no luck,

I never in my life have I heard caps on the cold side of a power board? What does that mean?

 

[Techie012]

I never in my life have I heard caps on the cold side of a power board? What does that mean?

Capacitors on the DC side.
The "HOT" side is the AC part and the "COLD" is the DC part.

 

[Techie012]

I replaced these two, with known good ones from a another broken Panasonic TV to no avail as stated above.

 

[Delta Prime]

Capacitors on the DC side.
The "HOT" side is the AC part and the "COLD" is the DC part.

Thank you for your timely response.
Your response is the exact point where Misinformation is born.
Nothing is defined; there’s too much room for interpretation.
I find it educational and intriguing. Thank you for your response..
Admittedly, I am just as bad; for I have left no academic references, for my observations.

 

[73's de Edd]

Sir Techie012 . . . . .

I recently a(c)quired a Panasonic TH-60CX700Z.
Was this fault immediately noticed, at the time that you first received and hooked up the unit . . . OR . . . has the unit been performing normally, and just now, has developed this fault ?

You do realize that this is being one COM-PLEX little puppy ! . . . . . and that's being 5 echelons of HEAVYYYY on the PLEX !

How about initially going to the P board and have - lead of a Digital VOM to cold ground and positive lead CLIPPED into
Test Point 7501 pin 2 for monitoring 5V.
Turn on the set and then see if +5V shows and holds or drops off when the problem is experienced ? . . . . Acknowledge.
Then keep same grounding and move positive metering lead , and clip onto . . .
TP7410 pins 11/12 for monitoring 16 V
Does that 16V presence drop off at problem time ? Acknowledge.

73's de Edd . . . . .

 

[Techie012]

Hi Mr 73's de Edd, thank you for your response.
The problem was emediate once I got the TV.
I have already checked the 16v and 5v presence as you suggested, the 5v stays at a solid 5.12 when the fault occurs however the 16v drops off.
I have all so noticed that the red stand by light blinks red once every 30 seconds after the problem occurs and I can turn the TV on again by holding down the power button on the power supply for 10 seconds.

Sir Techie012 . . . . .

I recently a(c)quired a Panasonic TH-60CX700Z.
Was this fault immediately noticed, at the time that you first received and hooked up the unit . . . OR . . . has the unit been performing normally, and just now, has developed this fault ?

You do realize that this is being one COM-PLEX little puppy ! . . . . . and that's being 5 echelons of HEAVYYYY on the PLEX !

How about initially going to the P board and have - lead of a Digital VOM to cold ground and positive lead CLIPPED into
Test Point 7501 pin 2 for monitoring 5V.
Turn on the set and then see if +5V shows and holds or drops off when the problem is experienced ? . . . . Acknowledge.
Then keep same grounding and move positive metering lead , and clip onto . . .
TP7410 pins 11/12 for monitoring 16 V
Does that 16V presence drop off at problem time ? Acknowledge.

73's de Edd . . . . .

Hi Mr 73's de Edd, thank you for your response.
The problem was emediate once I got the TV.
I have already checked the 16v and 5v presence as you suggested, the 5v stays at a solid 5.12 when the fault occurs however the 16v drops off.
I have all so noticed that the red stand by light blinks red once every 30 seconds after the problem occurs and I can turn the TV on again by holding down the power button on the power supply for 10 seconds, and then releasing and pressing it once quickly.

 

[player2move]

A one time blinking power led on panasonic led-tv's indicates a "BL_SOS" - set switches off after about 2 seconds.
Protect mode is activated if current for backlight is not within the specs.

You can check backlight with a service tool, e.g.:

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