Electric Window

[Richard Moakes]

Well, someone must have let a gremlin into my car !

The drivers electric window has suddenly stopped working, no slow running, no nasty noises beforehand, just stopped dead, thankfully in the fully closed position.

I swapped the switches around, and all I get with any switch is a 'clunk' from the door whenever I push the switch, and the motor is not running.

I have tried the slam door with ignition on and pushing the switch trick, but to no avail.

In hope I took off the door trim looking for something obvious, but all the wires are in good condition, and I can't see anything wrong with the guides or regulator.

So, what do people think?  Has the motor finally quit after 13 years of service, or has one door slam too many caused a problem with the regulator.

Any advise gratefully received before I have to spend money on replacement parts.

Thanks,

Richard
1989 300E W124

 

[Andy]

Hi

Sorry to be the bearer of bad news. I think the motor has given up!!!

May it RIP.

Regards

Andy @ www.mercedesservicing.com

PS. You could try giving it a couple of select TAPS with the hammer. You never know it might just breath life into it. But remember it may stop again. This time in the open postion.

Good luck!!!!

 

[dave elcome]

Richard.

I echo Andy's sentiments re the motor, and a "light tap", it's amazing just how many parts on a motor vehicle are designed to respond to "impact technology". If his method fails try mine.

About a year ago i had a problem with the electric windows on my old 250D (w124), i tried to swap the motors front to back, but they were different so this could not be done, i suspect this to be the case on your vehicle, but cannot be certain.

The window motor is basically a simple electric motor, which ultimately requires feed and earth to complete a circuit.  This circuitry is then controlled by relays etc, such that when you push the window switch in the open position it powers the motor to turn in a given direction, the window wnder mechanism, (commonly known as a regulator) then lowers the window. When you operate the same switch to close the window, the circuitry takes over again, but this time it supplies power to the opposite side of the motor causing it to rotate in the opposite direction. You've guessed it, the window now goes up.

What i did was to identify the wires that feed the motor, and disconected them, i then applied power directly to them from a spare battery, and saw that the motor opperated correctly in both dircetions.

I would advise you to try this first, as its simple and FREE, this will either rule out the motor, or confirm thats its the culprit.

Hope this is of use, and if the explanation of the motors operation was an "egg sucking" excercise, then i appologise.

 

[Richard Moakes]

Good news, a bit of percussive maintenance has got the motor working again!

Better get it replaced before it quits again, in the down position, and when it's raining no doubt!

Don't suppose anyone knows the part number?  It will save a bit of grief down at the new stealership. Frankly they are having trouble identifying specific parts of their own anatomy down there at the moment, so explaining what I want could be a trial ;-)

Strange, I keep repairing various bits, but my list of jobs to do never seems to get any shorter.

If I didn't appreciate the engineering so much, I would get disillusioned like I did with Vauxhall, now there is a car designed to fail and make it difficult to repair !

Thanks for the advice chaps, it is appreciated.

Richard

 

[John Turner]

The rear electric window in my W124 250TD stuck in the down position on Sunday night.  It has been intermittent for a month or so - usually requiring the switch to be held down for some seconds before it would lower but then working fine, except on wet days when it would not work at all!  I had left the window down for a few hours on Sunday, and it failed to go back up.  I checked switches, fuses  and relays, and then I too took off the trim, and got the motor going again with a light tap.  There were no signs of water penetration in the door, and so I assume the motor simply struggles more in high humidity. The motor seems to be working fine now and with the usual power.  However, is it living on borrowed time?   Am I right that these motors can stop in one position and sometimes not go again unless the position of the coil/commutator can be rotated a little (no doubt what happens when they are tapped)?  Was the earlier several second delay in the window responding due to the electric motor trying and eventually succeeding in turning?  Is there any way of repairing/cleaning  the motor, or is it a replacement job?  I had a new motor and regulator fitted on the front window on separate occasions last year (the motor simply got weaker and then stopped, and the regulator had worn, and these were expensive - about £88 for the motor and £45 for the regulator never mind labour costs!). It seems from the Forum that electric windows remain a bug bear in older Mercedes models!
I have had quite a few and expensive problems with this car over the 5 years I have owned it (from 92,000 miles to 133,000miles: 3 renewed door straps, head gasket, drive belt tensioner, drive shaft vibration coupling, front window regulator/motor, new radiator, door lock barrel and ignition switch, new fuses), all being problems regularly reported for W124s in the Forum, and some of which can be expected in a 13 year old car.  I do find it an excellent family estate, with extremely good interior and body work and it is now very well sorted (I hope!).

John Turner
Smoke Silver 1989 W124 250TD with 7 seats & sun roof

 

[John Turner]

The rear electric window in my W124 250TD stuck in the down position on Sunday night.  It has been intermittent for a month or so - usually requiring the switch to be held down for some seconds before it would lower but then working fine, except on wet days when it would not work at all!  I had left the window down for a few hours on Sunday, and it failed to go back up.  I checked switches, fuses  and relays, and then I too took off the trim, and got the motor going again with a light tap.  There were no signs of water penetration in the door, and so I assume the motor simply struggles more in high humidity. The motor seems to be working fine now and with the usual power.  However, is it living on borrowed time?   Am I right that these motors can stop in one position and sometimes not go again unless the position of the coil/commutator can be rotated a little (no doubt what happens when they are tapped)?  Was the earlier several second delay in the window responding due to the electric motor trying and eventually succeeding in turning?  Is there any way of repairing/cleaning  the motor, or is it a replacement job?  I had a new motor and regulator fitted on the front window on separate occasions last year (the motor simply got weaker and then stopped, and the regulator had worn, and these were expensive - about £88 for the motor and £45 for the regulator never mind labour costs!). It seems from the Forum that electric windows remain a bug bear in older Mercedes models!
I have had quite a few and expensive problems with this car over the 5 years I have owned it (from 92,000 miles to 133,000miles: 3 renewed door straps, head gasket, drive belt tensioner, drive shaft vibration coupling, front window regulator/motor, new radiator, door lock barrel and ignition switch, new fuses), all being problems regularly reported for W124s in the Forum, and some of which can be expected in a 13 year old car.  I do find it an excellent family estate, with extremely good interior and body work and it is now very well sorted (I hope!).

John Turner
Smoke Silver 1989 W124 250TD with 7 seats & sun roof