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Rudolf Ladyzhenskii
 
Posts: n/a
Default HP D5258a monitor is totally dead

OK. I know the one you are talking about. It is the one with 2.2M resistor.
(Daewoo CMC1520X)

Look closely on resistors near that UC3842 IC. It is a small resistor next
to it.
And AC filter capacitor will hold charge! Make sure you discharge it before
working on teh unit.

Rudolf

"Michael" wrote in message
...
Rudolf, the only markings on the power supply chip are as follows:

ST MAL
UC3842B
91C005

It is a 8 pin chip, I can't see any 0.33R near it.

I have checked the main fuse behind the power cord connector and it seems

to
be okay.

And I am staying away from the AC filter capacitor, as I cant get the

board
out to discharge it and I dont want to hit my head on our roof when I jump


Michael.

"Rudolf Ladyzhenskii"

wrote
in message ...
Hi,

I think, yours is that other chassis without 2.2M resistor. Does it use
STRS6707 IC in power suply?

If it does, most likely it is shorted. Also, there is a 0.33R resistopr

next
to it and a fuse that blow.
WARNING! If fuse is not blown, AC filter capacitor may contain full

charge
of 300V and will happily discharge through yourself.

Rudolf

"Michael" wrote in message
...
Hey, my HP D5258a monitor is totally dead. When your press the power

button
there are no whistles, clicks, led, flub-flub-flub noises, nothing at

all.

I have searched google and found a reference to "a small 2.2M resistor
beside the PS controller IC (R024)" going open circuit. However on

mine
the
lowest numbered resistor is 302, and the ones near the PS section are
numbered R850, R861, R809 etc.

Any ideas or can someone interpret the schematic for me please?

Michael.

Model No. D5258A
Product No. D5258-60012
Serial num. TH02001590
Manufactured May 2000
Chassis code C5B