problem with electric front window

Enright

looking for help here.
driving a merc 220cdi, this week i opened the drivers side window and it only closed half way, each time i pressed the up button it moved up several cms and then returned back to half closed.

after some time i noticed that if i pressed it up, released it, up , released it etc it closed fully.

Any suggestions as to my problem? cure?

is it a sensor?

milltown

Does it sound like the motor is winding it back down, or does it just seem to fall back down?
If the motor is winding it down it could be as simple as reinitialising the window (simple on most cars anyway, dunno about mercs), or else a faulty switch or trap sensor.
If it's falling back down you could be looking at a window regulator. Could be €€.

anthony4335

Take a look in your manual a see if there is a proceedure to reset the window height setting. This usually needs to be done if the battery has been disconnected. If this is ok, if might be something slowing the window causing it to think that it has hit soemthing , you will have to remove the door card for that and check the runners, and window lift. There is a chance it is the motor but try these things first, but a motor should not set you back more that 100 euro, and you should be able to replace it your self.

kenco

Can you hear the motor going when you try to raise/lower the window?

If so then it could be that the worm unit has worn away (common problem with Mazdas and Renaults)

I think it is around the €150 to replace it. There is a guy who used to do this on a call out basis, unfortunately I cant recall his name or contact details. If I find them I will post an update

Esel

Get some Holts Rubber and Nylon Lubricant (Silicone) in a motor factors. Great for freeing 'sticking' car windows. Not saying this is your problem, but it's a cheap thing to try.

Enright

to all who replied, many thanks, for the last few days now, it been perfect! i think it was (is) a faulty sensor, however, as its working im not stripping it down just now

crosstownk

I've seen this before - sometimes the door control unit needs to be reset. To do this you need to:

1. Lower the window keeping your finger on the switch and leave it there for 10 secs after the window has reached the bottom.
2. Repeat the above for the upward travel.

As pointed out above, if the window slots are dirty or causing excess resistance in the window travel, the motor will go into rollback mode and drop the window - it's a safety feature.

stratos

Yes same as crosstownk, also steering has to be reset by going from full lock to full lock. changing battery or start on a low battery seems to cause it as well.