Having an issue with left vuk on Hook not working. It works if I ground the signal wire of the coil both at the coil and j8 pin 12 on ppb board. However if I ground q44 or pin 4 of cn11 on CPU it does not fire. I've got continuity from cn11 CPU to j1 ppb. I've replaced q1 tip36c. D3 d11 and R3 all test within spec. I'm not sure where to go next....don't have another de machine to swap boards either.

I also replaced Q44 and Q36(predriver) again, and still no luck.

If i ground Q29 (the relay drive), then when i ground the Q44 transistor, it fires the associated flasher - does this indicate the problem is upstream or downstream of Q44 - or a coil wiring issue? I've double checked, and there is 75V both sides of the coil.

I am goign down the path that since i can't get it to fire at CN11, the problem is downstream of there (either PPB or coil) - but everything appears to check out. However, when i measure coltage at the tab of Q44 - its around 10v - others are 75V

11 (resized).jpg

Resolved. Was a real pain to find but cold solder joint at pin 11 of j8 on ppb board.

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