Where do I start?

One power window stopped working (Front Pasgr.).
Neither the master control or the door control will operate the window.
(Fortunately it stopped in the up location.)

But after two weeks the window is slowly sagging downward. Now it is down about 1/2 inch.

I know door wires can flake out. But both controls stopped operating at the same time and window is sagging.

Where do I start?
Thanks!

 

If the other windows work power is getting to the master drivers switch.

Might start by checking power and motor operation at the non-working door.

You can apply 12V directly to the motor via the red and green wires to determine if it is working.

Take note the motor receives power from two sources.

First the master switch powers the motor via green and red wires. Polarity is changed by this switch to rotate the motor one direction or the other.

Second a blue wire (constantly hot) from the master switch to the door switch. When the individual door switch is used the switch routes this power to the green or red wire on the motor (depending on direction desired). The return power goes back through the door switch to the master driver switch via the opposite wire (red or green).

The motor wiring is not grounded to the chassis at the motor. This takes place at the master switch.