# [SOLVED] Philips 42 FD 9953/69c Plasma Continuous Flashing LED



## Crossy (May 12, 2008)

Hi,

After many years of sterling service, my Philips Plasma has developed a fault.

When the mains power is applied to the unit and the power switch is pressed the red LED on the front panel lights. When the power button on the remote is pressed, the red LED turns steady green, then after about 10 seconds the steady green LED turns red again then continuously flashes red indefinitely.

I can hear various relays clicking from within the unit, but there is no sign of an image or any activity on the screen. The TV is then unresponsive to any button pushes on the remote. The only way to stop the continuous flashing red LED is to press the power switch on the unit again.

I have read many posts about bulging capacitors causing problems, and accordingly I have replaced 3 large caps on the main board (2 x 330 uf and 1 x 1000 uf) but this has not changed anything.

I have tried different power outlets as well, with no success.

I'd appreciate any suggestions, not averse to changing components myself but I don't want to invest hundreds of dollars fixing a 12 year old set.

Thanks in advance.

Rob.


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## JimE (Apr 16, 2009)

*Re: Philips 42 FD 9953/69c Plasma Continuous Flashing LED*

The User Manual only suggests removing power for 10+ seconds. So basically just a system reset.

To investigate further you would likely need schematics and proper test equipment.


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## Crossy (May 12, 2008)

*Re: Philips 42 FD 9953/69c Plasma Continuous Flashing LED*

Hi JimE,

Thanks for getting back.

Agree completely, I was just hoping to find someone who had experienced the same. There are many, many posts about other Philips models experiencing similar problems due to leaking/faulty capacitors, but this does not appear to be the same because the blinking LED in this case is continuous, whereas in the other cases there seems to be a blink 'code' (groups of 7 blinks).
I'll give it one more going over, check fuses, look for dry joints, measure voltages (there are a number of placards showing voltages inside the chassis) etc then it's off to landfill if I can't fix it.

Rob.


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## Crossy (May 12, 2008)

*Re: Philips 42 FD 9953/69c Plasma Continuous Flashing LED*

OK.

Note: The TV has begun working intermittently.

All fuses (that I could see) are intact, and there are no visible dry joints. Mains voltage checks out at 240 going onto the main board.
The Voltage check has shown one interesting anomaly. All measured voltages are within a bee's knee, except for Vsbsw which is placarded as 3.3v. At one measuring point it is 3.2v, but at another it is .65v

There are 3 Green LEDS (LED 8001. 8002 and 8003) and one Red LED (LED 8004) mounted on the main power board. When the fault occurs, the Red LED lights and LEDS 8001 and 8002 extinguish.

I have also noticed that some of the Electrolytic Capacitors are reading about ~1v on the metal body with respect to earth, while others show 0v. Is this significant?

I think I'll pull the main board again and see if I can find what is causing the anomaly with the Vsbsw voltage reading.

Rob.


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## Crossy (May 12, 2008)

*Re: Philips 42 FD 9953/69c Plasma Continuous Flashing LED*

EDIT:

Please disregard the note about the Vsbsw rail reading differently at 2 different points. Operator Error.

I'm leaning more towards the old 'failing capacitor' theory. I'm leaning towards if it was a semi conductor causing the problem, it would not work at all, whereas an aging capacitor could exhibit varying behaviour. Any comments?

Rob.


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## Crossy (May 12, 2008)

*Re: Philips 42 FD 9953/69c Plasma Continuous Flashing LED*

Encouraged by the fact that the set is now working intermittently, I assumed it was because I had replaced a faulty cap, thereby improving things.
There are 2 other 1000uf/160v caps (C8087 and C8088) adjacent to the one I replaced (C8087), so on speculation I removed these 2 and tested them with a DMM. I don't have a Capacitor tester, but the DMM showed a resistive reading from both capacitor terminals to the aluminium can, as well as a resistive reading between both terminals.

On this basis I have ordered 2 more caps which should be here in the next few days.

Rob.


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## Crossy (May 12, 2008)

*Re: Philips 42 FD 9953/69c Plasma Continuous Flashing LED*

Having installed the 2 x 1000uf caps with no further improvement, and a further 10 or so smaller caps also with no improvement, it seems to be destined for landfill.

A great pity because of its size, as well as the fact that it still gives a great image (when it starts).

Rob.


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## Crossy (May 12, 2008)

*Re: Philips 42 FD 9953/69c Plasma Continuous Flashing LED*

Had an 'Aha' moment when, after the set had started reliably during the day, it reverted to its faulty state at night. What was happening? Perhaps the lower temps (around 5c overnight) were the difference.
I recalled reading how another poster had used a hairdryer to warm suspect capacitors, so I borrowed my wife's hairdryer and got to work. Seems like when I warm the caps (2200uf, 100uf, 150uf and 470uf) around the SCAVIO supply, the set starts every time.
So back to Jaycar I go.

Rob.


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## Crossy (May 12, 2008)

*Re: Philips 42 FD 9953/69c Plasma Continuous Flashing LED*

Turned out to be a 22uf, 16v SMD electro on the Alarm board which is attached to the SMPS.

It was causing the Alarm board to crowbar the SMPS into protect mode too soon because it wasn't allowing all the individual voltages to time appear at their correct values.

Rob.


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## WereBo (Apr 5, 2008)

Hi Crossy :wave:

Glad you got it sorted and thanks for posting back with the cure, plus novel diagnostic methods :grin:


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