Panasonic TH-42PZ8BA help!

[netdent]

Need some help with this one, first panasonic I have opened up! it powers on as it should to steady green light but screen is blank, have measured 203volts to both sus boards and checked the psu fuses I'm stuck now, not tried to connect video to see if sound present due to no dvd spare to try but will need to find one, any help welcome

P.s green led lit on each y and z sus

[PlainBill]

Re: Panasonic TH-42PZ8BA help!

Need some help with this one, first panasonic I have opened up! it powers on as it should to steady green light but screen is blank, have measured 203volts to both sus boards and checked the psu fuses I'm stuck now, not tried to connect video to see if sound present due to no dvd spare to try but will need to find one, any help welcome

P.s green led lit on each y and z sus

Good quality pictures. A couple of things you might want to check: In the lower left corner, between the two transformers and to the left of the orange capacitor, it looks like a dead worm is wrapped around ??? Above the upper of the transformers, near the top of the board, the white rectangular ?resistor? looks like it might have been dislodged.

PlainBill

[netdent]

Re: Panasonic TH-42PZ8BA help!

Hi Bill, yes the worm is actually a bead of silicone type stuff! I noticed the resistor too but it is securely soldered.

thanks Ronnie

[netdent]

Re: Panasonic TH-42PZ8BA help!

This one is back on my bench before I decide to strip it for parts! can anyone help please

thanks Ronnie

[netdent]

Re: Panasonic TH-42PZ8BA help!

Just to update, the screen does light to dull luminance no sign of menu etc

[rayrod81]

Re: Panasonic TH-42PZ8BA help!

This points to a problem with the D-board. The fact that the LEDs on the SC and SS boards are lit mean that they are most likely working properly.

[netdent]

Re: Panasonic TH-42PZ8BA help!

This points to a problem with the D-board. The fact that the LEDs on the SC and SS boards are lit mean that they are most likely working properly.

Thankyou for the reply, not sure which is the D board sorry, is this the main av board or the psu, I suspect the av board, if I unplug the ldvs cable to the main board I get a full white screen

thanks Ronnie

[rayrod81]

Re: Panasonic TH-42PZ8BA help!

The D-board is the control board of the plasma. It should be behind the cage that houses the main board or av board.

[netdent]

Re: Panasonic TH-42PZ8BA help!

The D-board is the control board of the plasma. It should be behind the cage that houses the main board or av board.

Ok great thankyou, is there a sure way to verify as faulty ie status led etc, just want to be sure before looking for a replacement


thanks Ronnie

[netdent]

Re: Panasonic TH-42PZ8BA help!

just a thought! if the control board was at fault I should get sound if I feed a video signal?

[rayrod81]

Re: Panasonic TH-42PZ8BA help!

No way to test it that I know of. There should be a troubleshooting diagram for no picture in the service manual for this generation of plasma. You can find it at elektrotanya.com. Search for the TH-42PZ80U it is the same chassis and parts as the TH-42PZ8B. Make sure you download the service manual for that TV and not the training manual for the entire PZ8xx series. I have run across this problem a couple of times in the past and the D-board was the problem.

[rayrod81]

Re: Panasonic TH-42PZ8BA help!

Not sure on the sound. I would think so but can't be sure.

[netdent]

Re: Panasonic TH-42PZ8BA help!

Not sure on the sound. I would think so but can't be sure.

Thankyou rayrod81 I will look into it and see what I can find, be nice to get this working has been on the pile a long time

thanks Ronnie

[netdent]

Re: Panasonic TH-42PZ8BA help!

Ok the flow chart points to the D board, thanks for the advice, will order and report back

Ronnie

[tom66]

Re: Panasonic TH-42PZ8BA help!

That's a weird PSU, I've been trying to figure it out. I don't see any diodes for the secondary output, anywhere... and I see a lot of holes where diodes could go. Also, no PFC stuff but places for them. Has someone decided to remove all these components?

[rayrod81]

Re: Panasonic TH-42PZ8BA help!

Most of the components on these Panasonic PSUs are soldered in from underneath and attached to the large metal shield that also acts as a heat sink.

[netdent]

Re: Panasonic TH-42PZ8BA help!

just another thought guys if I scart this set to another set should I get the panasonic screen

[netdent]

Re: Panasonic TH-42PZ8BA help!

The control board is ordered, was unable to get any audio connecting a dvd player but its difficult to know the tv is on correct channel? also tried scarting to another set but still no joy, bit of a gamble just hope the part cures the fault

Ronnie

[netdent]

Re: Panasonic TH-42PZ8BA help!

Ok the D board came this morning, still not working!!! my gut instinct was av board? question is do I now order this or cut my losses?

cheers Ronnie