Quoted from pinmike:
Some transistors test good when they are bad.
Power off set meter to continuity place black probe on ground(strap in the backbox).Touch red probe on the tab of that transistor if it beeps it means it’s shorted
This works for lamp rows. But you have to check continuity between the tan and the lamp matrix power for this to work on a column. You can use any of the pins on the right side, second connector up from the bottom.
Chris Hibler - CARGPB #31
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