Philips TV shows a white screen. Any advice welcome
P. Pirotte
I try to fix a modern Philips TV set (2 years old). The references of
this set are: G90AE, UVSH, 21GR2350/20B.
The symptoms could be described as below:
The screen remains deseperately white and bright. No sound available.
Neither the front control knobs of the TV set nor the remote control
seems to have an effect (channel selection, volume, brightness,
contrast, standby, search......). The LED indicator who was normaly
blinking when using the remote control doesn't react anymore (I've
check my remote control on another Philips TV set with success).
Inside the TV set, the power supply check points (5, 12, 22, 95 volt)
are correctely powered.
The sound IC is correctely powered too (I think the sound is probably
blanked by the microcontroller).
As the power supply seems to work perfectely and, as the Very High
Voltage is allright, I suspect the microcontroller to be guilty...
I didn't find any reset swich and there is no backup battery for the
memory. It must be an EEPROM memory... Just near the microcontroller,
there is a small IC (dil8 case), it could be the memory (serial access
type memory). I cannot read the reference of both the microcontroller
and the other IC (memory) as there is a thin metallic plate glued on
them (radiator).
What do you think of all this story... Is there an easy way to be sure
the microcontroller is dead (An answer like: "replace it and try..."
doesn't interrest me at all). Is there an easy way to reset the
microcontroller and his memory. Where is the memory (inside the
microcontroller or is it the small IC just near it)? Do you have any
interresting advice to help me with this neon-light-look-alike TV set.
Thanks.
Pascal.
N.B. Sorry for my poor english....
woody
Despite your preferences in replies, you are probably right that the uController has died -
not an uncommon problem. You will have to go to a Philips dealer for the part as it is
probably a generic controller chip that is either mask or fusible link programmed to your
chassis type and version. IME there is no means of restarting the uC/E2PROM.
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