E32 power window regulator or motor replacement

Symptoms: problems with window

Goal: replace the window regulator and/or motor.

Performed on: '88 735i

Applies to: All E32 cars: 735i, 735iL, 740i, 740iL, 750iL

Disclaimer: I do not assume any responsibility for the correctness of these instructions or their applicability to the specified models. Use at your own risk! Also, use commons sense, don't do stupid things.

Instructions

• Before beginning, roll the window almost all the way up if you can
• Remove the door panel (see my "Door panel removal instructions")
• Unscrew the 4 nuts that hold the window regulator assembly to the metal part of the door. These are 10mm nuts.
• Wiggle the whole assembly around, then move it sideways to get the upper end of the regulator out of the 2 rails that are attached to the window glass. Soon enough the assembly will become loose.
• Disconnect all cables from the assembly. The motor will be hard to disconnect so you can wait to do that until the whole assembly is outside of the door
• Take out the whole thing (if you're having trouble fishing it out of the opening, with the motor cable connected, press the button that lowers your window, but KEEP YOUR FINGERS AWAY FROM THE ASSEMBLY as you do that; the glass should NOT go down and the assembly should be easier to take out)
• Installation is the reverse of removal. It'll take some time/effort to reinsert the plastic guides into the rails... you kinda have to insert both at the same time, otherwise they pop out. You also have to move one of the arms of the regulator to align with the hole on the door. It's easiest if the window was rolled up to the same position on the new assembly as it was on the old one. If it's not, connect the cable to the motor and press the "up" button to make the assembly "roll up" almost to the top. Then you'll be good.
• Note that if you're playing with the window when only the motor is connected, it won't go all the way; it will just move in small increments. This is due to the fact that the sensor that tells it whether it has reached the top/bottom position is disconnected, so it assumes that it has reached the end position and stops moving.
• If you're replacing the motor only or need to take the motor off of the assembly for whatever reason, you'll need to connect the motor's cable (as the whole assembly is out of the door), then press the "down" button to move that cog wheel in a position where you can reach the third screw that holds the motor. Again, keep your fingers out of the way of the moving parts.

You're done!