Electrical: Recent intermittent electric window prob now permanent.

[c_lee]

One of my 1988 240 GL's has developed an electric window problem on the driver's door.
Initially, about a month ago, the problem was intermittent, caused little inconvenience, and could be overcome by re-opening and closing the door.
The fault is no longer intermittent and has left the driver's door window down about 1 inch.

Being that I rarely park in risky areas and leaving nothing on display in the car and that I'm involved in a property renovation at present I intended to give it the once over when time permitted.

My other 240 GL had a fault with the same symptoms about 12 months ago and I assumed the fault was probably the same but not so.
In that case regular flexing of the wiring loom at the driver's door hinge had caused an intermittent fracture of a wire in the loom. Now fixed.

In the last couple of days I realised that someone poking a wire in the window gap to operate the internal door release would also have access to the boot in the way I used the boot lock. Once realised I made sure the boot lock was isolated from the central locking system by using the fully anti-clockwise position of the boot lock.
This nudged me into getting my multimeter out today to investigate.

The voltage and earth on the window switch is present. Ohm meter readings on the wires feeding the motor at the window switch are infinity ohms. Checks of ohm meter reading on the wires immediately on entering the motor are infinity ohms.
Obviously a motor problem.

The check I did today was about 2 hours before I was due to leave for work so I had to mainly leave it at that as the Haynes manual says you need to have the window in the lowered position to enable you to extract the motor mechanism ( how do you lower the window then if the motor has failed )?

As a final step I decided to give the motor a hammer tap and it then operated.

What, in the construction of the motor, is likely to have come good and made it work. Anyone had one apart.

The obvious that comes to mind is sticking brushes in their holders but what else should I keep in mind.
Is there an opening in the motor case accessible whilst in place where I could squirt some WD40, couldn't see one.

I don't want the intermittent fault to re-occur as I could then be faced with the window stuck fully down sometime in the future whilst about to park up.


When time permits I will remove the mechanism to investigate fully and hopefully effect a repair.

Any suggestions.

Colin

[wooble]

While I don't know much about the window motors, I have heard reports in the past of the permanent magnets inside the motor can of 240 wiper motors coming detached causing similar symptoms, and it being fixed by simply opening up the motor, cleaning it up and glueing the magnets back with epoxy resin.

if you've got the motor working now, A trick I've used myself in the past is to detach the glass from the regulator mechanism and wedge it in the closed position with two wooden dowels cut to length between the bottom of the door and the glass, so your car is secure and you can remove and repair the mechanism at leisure.

[Cyprusbob]

My first 240 glt had this problem and there is no easy fix, its more likely to be a broken wire in the loom where it passes throught the door, there should be a flexi boot between the top and bottom hinges which con be prised away from the door and carefully cut the nylon mess from the loom and if you are feeling lucky you will find it quickly......
Good luck

[morsing]

I had this problem on mine last year. You need to take the whole window mechanism out, remove the wiper motor CAREFULLY (follow Haynes guide), slide the brush cover back (can only be slid half-way back) and clean the contact with a wirebrush.

Good luck.