power window problem

["Shahrol Halmi" <alfalist@domain.elided>]

The passenger side (left side, RHD car) power window on my '92 33 has
stopped working.  What I've done:

1.  Check the relay controlling the power windows - the one with the
attached fuse.  Looks ok.  As the driver's side window is working fine, I
doubt if it's a fuse problem

2.  Check the voltage at the switch(es) at the doors.  The voltage is +6V
between the blue leads (I believe these are the wires connected to the motor
on the passenger side) when the switch is set to push window up (window is
currently all the way up, and I can hear the motor clicking).  Conclusion,
current is going to the motor, voltage dropped since the motor is trying to
push the window snug against the doorframe.  This is a good sign.

3.  Voltage when switch is thrown to open window, however, is stable
at -12.6V - conclusion, switch, relay, power working normally, but the motor
ain't taking the volts and reversing itself.

Question is - is there a relay or cutoff switch that's stuck which is
preventing the motor from seeing the -12V?  Is the motor going bad?  Is
there any other diagnosis I should go through, other than replacing the
power window motor?

Shahrol
Kuala Lumpur, Malaysia

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