power windows/sunroof wires

Huw Powell human747 at attbi.com
Sun Jun 23 00:14:16 EDT 2002

> Huw, I can see why you might think that. Probably I should have told you
> that both doors are out and that I have already tried bypassing the
> switches altogether by using jumper wires on the connectors. So the
> switches are not the problem.

> Anyway, the passenger door doesn't get its power through the driver side
> switch. It's only the two ground wires that go through the driver side
> switch. The power supply wires in both sides connect, along with the power
> supply wires for the other windows, the sunroof, and the power supply wire
> coming out of the window control unit, at the same place; but I don't know
> where that is in the car.

whoops, got it backwards, sorry about that.

You'll have a tough time digging out that splice... it's gonna be deep
in some inch thick chuck of harness, I suspect.  From what those
crimped/welded junctions usually look like, I would imagine it has not
failed, either.

if, however, it managed to get wet or something, all bets are off.  I
must have one of those harnesses around here somewhere, let me see if I
can guide you to that junction point...

OK, I got most of one of them in my hands now... yikes!  well, the tape
on it is blue... it's all chafed up where it went thru the driver's door
jamb area... and a bit too much is missing... sorry.

So, getting back to that bad power wire.  When you measured it to
ground, did you check to make sure your ground was good by measuring a
good source of 12v as well?  I usually do, to verify the measurement.

Have you checked that the ground wires are truly good?  To do this you
need to run current down them - use each one to ground the window motor,
using a good source of 12v.  it is possible for wiring to "measure" good
but to have insufficient current carrying capacity under load.  btdt
with some taillight wiring.

> Perhaps I should clarify the second paragraph from my previous message
> (below). There are five wires in each switch. In the passenger door there
> are two wires going to the motor, two wires which are grounded through
> the switch in the driver's door, and the red/blue power
> supply wire. When you operate the switch in the driver's door, the power
> goes through the aforementioned ground wires. So when you operate the
> driver's switch, the power is coming from there, but when you operate the
> switch in the passenger's door it is the ground connection that goes
> through the driver's switch, not the power.


> Now a defective driver's side switch could explain why I did not read a
> voltage from the red/blue wire in the passenger door if I had been using
> the ground wires as my ground source. However, there are lots of other
> ground sources available to use and I used those, not the wires in the
> connector. So you see, it is not the switch.

actually, to truly prove it isn't the switch, move it to another
location and see if it passes the grounds along properly there.  then
swap in the switch from the other slot and see if the remote switch in
question works yet...

Huw Powell



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