Power window motor

[SteveJ]

I figured I was in a unique position to get more information about the failure of the window motors because the motor I transferred to the rear door continued to malfunction predictably by stopping part way up or down. So I took apart the rear door again and opened the motor. All seemed correct and the brushes were in good shape. So I proceeded to adjust the endplay of the armature which seemed quite loose. Upon reassembly it did not change behavior and continued to stop randomly.

Two conclusions can be drawn. First that my theory of water being the cause is incorrect because the motor was bone dry throughout.

Second that armature endplay is not the problem as we had speculated in previous posts on this subject.

The simple dumb conclusion is that the motor just gets tired and replacement is the solution for the backyard mechanic.

[adallak]

I am just wondering is this problem common in other cars? What if GM just put one of motors from other cars which proved to be good over years? IMO knowing the problem and doing nothing about it is nuts! What do you guys think?

I did not see the motor and really do not understand what "tired" one is about. But it really looks like something gets hot and needs to cool down to operate again. Looked also to me like the motor drains some bad capacitors which need time to regain the charge, but there are no capacitors there.. <_>

[KHE]

The driver's window receives the most use of the four - that would explain why it fails sooner than the other three. I wonder how much wear & tear the auto down feature puts on the motor? It relies on stall current of the motor to turn off the power.

[Barry94]

I was the guy who fixed the end play in the motor and it worked.

Unfortunately it looks like it was an isolated incident.

In your case it sounds like a bad connection within your motor.

Likely one of the wires that make up the armature has a bad connection.

Since it is intermittent, then trying to find that is nearly impossible.

Barry

[jgr7]

When you had the motor out did you raise and lower the window by hand? This could tell you if you had some binding in the window regulator that might load up the motor causing it to shut off like it's supposed to do.

Jeff

[adallak]

I was the guy who fixed the end play in the motor and it worked.

Unfortunately it looks like it was an isolated incident.

In your case it sounds like a bad connection within your motor.

Likely one of the wires that make up the armature has a bad connection.

Since it is intermittent, then trying to find that is nearly impossible.

Yes Barry, looks like your research helpes to fix only a part of the problem. What if really constant use of the feature makes some mechanical parts to wear out increasing friction and consequently the load on the motor? Did anybody try to lubricate window parts? But ... StevJ used the drivers motor at rear window (which has not been used as much as drivers one) and the problem was just exported to the rear window... mistery