Viewsonic P810 Clicking
 

Make: Viewsonic
Model: P810-2E
Chassis: HV8SA
Other #: TNPH0089-4 (on chassis)

I get a relay clicking sound from RL571 on power-up. No lights, no screen etc'.

I'm relatively new to monitor repairs and would like some help on where to start.

I only have a basic multimeter.

I noticed that certain capacitors (C580, C582, C709) registered +3.8volts on their can tops, whereas no others do.

Is this normal?

Any and all help greatly appreciated.

Regards,

Kev :)

99% of the G810 and P810 failures are the flyback.
Do a google groups search for those model numbers and how to test the
most common failure mode of the flyback. It runs about $80 plus S&H.
About 10% of the time when the flyback fails, it takes out other parts
in the hv and power supply.

kvonb wrote:
Make: Viewsonic
Model: P810-2E
Chassis: HV8SA
Other #: TNPH0089-4 (on chassis)

I had a P810-1M monitor. Im not sure if it is different from yours.
Check the FCC number. Mine is GSS21001 August 1996
It has the same chassis number.
I do have a service manual and schematic for mine.
Check the FET transistor that drives the flyback transformer.
E-Mail me if you need more info.
John

Thanks for the reply John,

My FCC ID is GSS21001 August 1997, so same number but a year younger if that makes a difference.

I've done some testing against a manual that I found on the 'net and it seems that I am getting only 14vDC at Q820 (2SC4620) where I should be getting 125vDC!

This transistor seems to drive IC820 (STR-S6531) which I can't seem to find any information on.

However, when I connect my multimeter between any side of R806 (336vDC) and earth (on volts DC scale), the clicking stops and the degauss circuit seems to operate as normal!

I have the thing in a million pieces right now so I don't know if the screen is actually working when the clicking stops so I can't say for sure, but it seems to temporarily cure the problem.

I'm going to investigate this a little closer but any further help would be greatly appreciated.

Regards,

Kevin :)

I got power back to the mainboard, but as predicted the flyback is now the problem.

I'm running through all the supporting components to see if it is merely a supply problem.

Kevin :)

I tested the secondary side of the flyback with both diode and resistance tests (+ve and -ve directions), both show open circuit.

The primary side is good.

So I guess it's new flyback time :(

Any suggestions on where to get one?

Kev.

"kvonb" wrote in message
...

I tested the secondary side of the flyback with both diode and
resistance tests (+ve and -ve directions), both show open circuit.

The primary side is good.

So I guess it's new flyback time :(

Any suggestions on where to get one?



Actually it sounds like your flyback is just fine, the HV rectifier diode
has a forward drop quite a bit higher than a multimeter can supply, so it'll
test open circuit. If it's testing low impedance then you have a problem.

Well that's good news about the flyback.

My greatest problem right now is that I cannot test a pulsing voltage.

I have a problem flow chart but I need to be able to test a 0 to 47v pulse and I only have a standard DMM.

Any suggestions on how to do this?

Regards,

Kev.

Well after a week of messing around I replaced Q690 (IRFPF50) with a 2SK1217 and got power back to the mainboard (power LED on, degauss then into power down mode but no CRT).

I found a blown resistor (r861 .33 1/2w) which supplies 210volts from the secondary side of the main xformer to q855 and the (I think) horizontal & vertical driver (pulse?) circiut, and also to q680 which somehow connects to the flyback EHT_+B and q690.

So now the new q690 is blown and I'm back to the clicking and no power!

Back to where I started.

The flyback seems to test as good after following instructions from people who replied here earlier (thanks for all your help).

Any ideas anyone?

Regards,

Kevin.