Still need HELP with the rear driver’s window on my 05 XJ8. I have done extensive testing, but the glass will lower or rise only with repeated pushing of the window switch on the driver’s door and/or the door switch. When it moves, the glass will lower/rise about 5". I have to keep using the switch(s) to make it go further! Again, movement is only about 5" each time. I am at a lost what is happening! This is what I have done:

1. Used another window motor.
2. Replaced the driver’s door switch.
3. Hard reset by removing neg on battery putting neg/pos together.
4. Ran both motors detached from the regulator.
5. Removed fuse for that door to maybe reset it.
6. Tried the “global” closing/openning of the
   windows. The left rear does the same. Other windows and sunroof work perfectly.

Still no joy!

Any more ideas? I have looked at the electrical schematic, but did not find anything!

Richard

 

The only other thing I can think of is that window is finding it particularly hard to slide up and down within the guide channels, creating higher motor current draw that is perhaps being detected as a "foreign object" being jammed in the window stopping for safety.
Possible contamination in the window guide rails or glass edges, or something bent in those channels creating higher friction than normal.

Is there a possibility someone has spilled something on the window (inside or out) that has "gummed up" the window guide rails?

 

As noted, I tried both motors REMOVED from the regulator, and they did the same (moving about 5" each time I used the switch from driver's and rear door)! I am dumbfounded what is going on. I have ordered another motor! We will see if I have two bad motors!

 

Is the glass harder to move up and down in that window compared to the other rear window?
The electric window systems have a safety overload feature to halt their operation if they detect an obstruction such as an occupant's arm or something else caught in the window's path.
Your window behavior could be that very safety feature interrupting the window movement, but instead of something being in the way, you might have some kind of additional drag impeding that window's movement.

I had something similar on a rear window of my Toyota 4runner, but in my case not only was it a lot of crud in the window's lower channels (dirt and dog slobber), but the metal channel inside the door (two piece construction) was distorted and adding some binding force to the window.

 

Repeat from comment above:

I removed the motor completely away from the regulator. The motor was not bolted onto the regulator. It was just plugged in with the gear free. Therefore, no obstruction. It did the same with stopping every 5".

 

Is the 12v supply cutting out under load?
Try swapping relay?

 

All the other windows work perfectly! Does each window have a relay? If so, where would it be located?

 

The drive relay is incorporated inside each windows motor drive assembly, accompanied by the motor controller.
The embedded motor controller must have some intelligence to detect overload conditions along with perhaps storing window position and opened/closed limit reference information.

External of the window motor controller there are only door switch packs that control window movement, along with system override like global close and rear window inhibitor switch.
Nothing that I can see that would cause the 5" of movement then pause behavior that you are seeing.

That to me seems to be a window regulator that is trying to find its position.....it is just hunting for an end stop perhaps.
Refit the window motor, then press the down button until the window reaches maximum down position....hold down that down button for 5 an additional seconds, then press and hold the up button until the window rises to its fully up position and again keep the up button pressed for an additional 5 seconds.
Hopefully the integrated window control module will now know the range of motion of that window and work normally.

 

Scan the vehicle for fault codes-may give you an indication of where the problem is.

 

UPDATE:

The problem was the window motor! I was thinking it was odd my replacement motor was bad, but it was indeed! I bought a certified working motor. It now works perfectly! As mentioned, the motor has a computer board which sends signals for the motor to move the glass. I am assuming the board had a bad capacitor or a crack in the board??? I should try to repair the board!

I did try to reprogram the window, but it still would only move about 5" at a time as it did with the "global" opening/closing!

THANKS to all who took the time to help!

Richard

PS Hope this will help others with same issue