(Topic ID: 252098)

TAF opto issue


By monkfe

4 months ago



Topic Stats

  • 5 posts
  • 2 Pinsiders participating
  • Latest reply 4 months ago by monkfe
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#1 4 months ago

So I recently got my TAFG back together after a full teardown. I've resolved most of the minor issues, but my bookcase optos are being flagged during the startup test. I replaced both the opto boards when I had it apart. I confirmed the transmitter leds are all functioning (video camera). I removed the opto board and while replacing the 339's with sockets I found a physically broken resistor (R2 which I replaced, but no change). all diodes are good(via DMM test) on the board and the other three optos on the board are working properly and my led is lit as it should be. So what should I be looking for on the receiving transistors from the bookcase voltage wise. I've read where these can sometimes be installed incorrectly on the board, but I didn't specifically check that when checked to see if I had it wired correctly.

#2 4 months ago
Quoted from monkfe:

I've read where these can sometimes be installed incorrectly on the board, but I didn't specifically check that when checked to see if I had it wired correctly.

Do they work in Tests - Switch Edge ? If so they are wired correctly.

I'd be thinking reseat connectors at opto driver board, to CPU. If that doesn't do it, then I'd concentrate on the harness from them through the bookcase to a connector below. When it turns at start up, a connector or wire may be stretched enough to not work briefly. Those wires could have a break inside the individual wire casing you can't see.

LTG : )

#3 4 months ago
Quoted from LTG:

Do they work in Tests - Switch Edge ? If so they are wired correctly.
I'd be thinking reseat connectors at opto driver board, to CPU. If that doesn't do it, then I'd concentrate on the harness from them through the bookcase to a connector below. When it turns at start up, a connector or wire may be stretched enough to not work briefly. Those wires could have a break inside the individual wire casing you can't see.
LTG : )

They do not work on the switch edge test, but the other three do.

#4 4 months ago
Quoted from monkfe:

They do not work on the switch edge test, but the other three do.

Tear apart. Start over. Figure which way they go. You may need to check with a meter. Some are unmarked, some have the marks in different spots.

LTG : )

#5 4 months ago

ok i figured it out...I transposed the ground lead and put it on the opposite end....either the aftermarket board is different or I did it in my head when I looked at the pic i had taken... I just looked at the common to all the transistors and it was readily apparent. Thanks gents

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