Sanyo 20ez--Testing Q902 (An Idiot's guide to Stupidity)

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Sanyo 20ez--Testing Q902 (An Idiot's guide to Stupidity)

I've got a Sanyo Motitor with a blank screen. I somehow shorted it testing the B+. Small fuse (300 ma 125v) is blown.

I'm trying to test the Q902 per Dokert's flow chart but I'm stuck. Power is off. I've got the black lead to the metal frame of the chasis, and the red lead to what I thought was the case of the Q902 but I'm getting nothing. Just to prove that I'm an idiot I did the same test on my working Sanyo 20ez in my other cab and I still get no reading. I'm obviously doing something wrong because I should be getting a reading from my good Sanyo.

Here's my chasis
picture.php


Can somebody locate the Q902 for me and tell me where I need to put the red lead?

Laugh out loud (sob).
 
Thanks for the link. I can't even locate q902 though. I don't see it labeled anywhere on the PCB. Is it the circular metal deal on the right side above the flyback with the red, yellow and black wires? I see where the wires connect to the PCB it says "B" (Yellow Wire) "C" (Red Wire) and "E" (Black Wire).

That corresponds to what you said in the other post
buffett said:
turn the chassis over look at the 3 legs it should say

B red lead here
C black lead here should read.537ish.
E black lead here should read.537ish.

Does this mean I need to pull the monitor to test it?
 
From your picture, Q902 is on the other side of the board on the large metal heatsink. It is the three legged black thing that is screwed into the heatsink. When you find that, you turn the chassis over and you will see the three legs labeled B C E. These are where you put your leads. Nothing needs to be plugged in and your multimeter needs to be set in the diode mode.
 
From your picture, Q902 is on the other side of the board on the large metal heatsink. It is the three legged black thing that is screwed into the heatsink. When you find that, you turn the chassis over and you will see the three legs labeled B C E. These are where you put your leads. Nothing needs to be plugged in and your multimeter needs to be set in the diode mode.

Are you sure that's not Q901 on the left side by the heatsink?

SanyoBoardControls.jpg
 
Put your red lead to the top of Q902.(see picture)
 

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Are you sure that's not Q901 on the left side by the heatsink?

Oops, sorry. I shouldn't be giving anyone advice on this. I'm out.

LOL, you're miles ahead of me.

Thanks Tomtime. At least that tells me I was right about Q902's location. My mulitmeter just gives me 00.000 reading no matter what I do. It's like that when I turn it on, when it touch the red to the black lead, when I try to test my bad Sanyo, and when I try to test my good Sanyo. I could be that my multimeter sucks but it's much more likely user error. Haha.
 
Tip

If your really having a tough time testing a component, remove it and test it off the pcb.. I couldn't understand why every hot I tested on sharp monitors was shorted.. Removed the hot, tested it off the pcb and it was fine..

Last ditch effort if your stuck.. I wouldn't pull stuff off unless your really having trouble.
 
I'm learning a lot here. The 500mA/250v fuse in my multi-meter was blown (I'm guessing from the same incident) which is probably why I can't get a diode reading.
 
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