Panasonic TC-55CS560C (Dead No Standby or Blinks)

[Andrew F. Ali]

Re: Panasonic TC-55CS560C (Dead No Standby or Blinks)

Think you will need to get correct board.

Luck guess I see. Guess you had none to lose.

[tbj12]

Re: Panasonic TC-55CS560C (Dead No Standby or Blinks)

I'd prefer to call it an educated guess. Wouldn't have had a clue without the technical manual posted by dskall.

[Ian Paul]

Re: Panasonic TC-55CS560C (Dead No Standby or Blinks)

Would I be taking a serious risk to run a jumper from PDM A to B?

Not too sure what damage may be caused by jumping the pins.
LED Driver basics:-
A constant DC voltage from a DC-DC converter booster supply is fed at one end and a pulse-width-modulated, PWM pulse is fed at the other. The instantaneous difference between the two inputs determines the brightness of the LEDs. The PWM pulse is generated by the backlight dimming control (E-PWM) which itself is controlled by the video processing section via an I2C bus. By changing the width of the pulse the general brightness of the image can be varied.

[budm]

Re: Panasonic TC-55CS560C (Dead No Standby or Blinks)

Your TV does not have 8-zone drive setup so it uses only two PWM signals.
PWM1 (A) for 4 sets of LED 1~4
PWM 2 (B) for another 4 sets of LED 5~8
So the board that you bought does not have that that is why you had to jump the PWM signal to drive all 8 sets of LEDs, nothing to do with "The instantaneous difference between the two inputs determines the brightness of the LEDs"
Some model of these TV with back lit can do up to 8 Zones individual Dimming so they can claim phony high contrast ratio spec, your TV uses Edge lit.
BTW, Video Brightness control is not the same as Backlights level control.

[tbj12]

Re: Panasonic TC-55CS560C (Dead No Standby or Blinks)

Your TV does not have 8-zone drive setup so it uses only two PWM signals.
PWM1 (A) for 4 sets of LED 1~4
PWM 2 (B) for another 4 sets of LED 5~8
So the board that you bought does not have that that is why you had to jump the PWM signal to drive all 8 sets of LEDs, nothing to do with "The instantaneous difference between the two inputs determines the brightness of the LEDs"
Some model of these TV with back lit can do up to 8 Zones individual Dimming so they can claim phony high contrast ratio spec, your TV uses Edge lit.
BTW, Video Brightness control is not the same as Backlights level control.

As I said earlier, this is the same board as the one that came out of the tv. Only difference was the 14 pin connection on new board vs 16 pin connection on the old board. The new board with 14 pin connector did have empty slots for pins 15 and 16. I could've just swapped the connectors, but don't trust my solder skills enough. The jumper was a much easier fix for someone with my skill set.

The screenshot below from PDF you posted even lists both the TC-55CS560C and TC-55CS540C. I could be wrong here, but everything looks identical to me.

I'm sorry for the lack of proper technical terms. I usually stick to repairing tv's with bad caps, so I'm out of my element here.

[dskall]

Re: Panasonic TC-55CS560C (Dead No Standby or Blinks)

That's how we learn by getting out of our comfort zone.