I get about 6.5v when I first press the button, obviously it goes to zero as the window is not moving and the BCU thinks it is all the way up or down. This is at the connection just before the wire goes into the door, C0463.

I appears that I should have 12 volts. When I backstab the wire directly from the BCU for the drivers side, I get about 12v to start. When I backstab the wires for the passenger side, I get about .1v. This is at C0664, the connection from the BCU to the two windows.

I have connected a new motor to the final wiring harness before it goes into the door. It does not activate when I connect the new motor directly to the wiring harness. It seems like the BCU should put out 12 volts, given the window will operate fine with 12 volts.

Does this mean that the issue must be the BCU? That would mean that the other BCU I tried had exactly the same fault? Is that more likely than some other error? I took one apart and did not see any dry solder joints or other obvious failures.

Thanks for the insight.