HELP! 98 500SL driver's window won't work

[lepps]

My driver's window won't go down. Mechanic says it's the soft top control module but the passenger's window works fine and the top goes down a third of the way and stops only because the driver's window won't go down. I sent module out to be tested and was told it tested fine. Mechanic says they tested everything and replaced my soft top module with a test part and the window worked fine so therefore it must be my soft top control module. A new module costs around 2500.00 and a rebuilt one is approx. 1100.00. Please help! I can't afford either. I was told the soft top module only controls the right window and the soft top. I was also told it might be the limit switches. Any advice???

[tecqboy]

I have a 91. In my car there are seperate fuses for the left and right windows. If they ( mech's ) really changed the module and it worked, then it can't be the fuses. But I'd test the fuses. In my 91' they are in the trunk on the upper right side. Your car is newer and may be different. There is a lot of info in this forum on problems with the controller, the soft top, and the windows. The system controllers evolved through the years with the later years being a bit more complicated, so be sure you get info for your model year. But trouble shooting the system isn't too hard with the info you'll find here. Do a search with key words like soft top controller. Can you hear the relays ckick when you operate the window switches? The relays are on the controller under the right rear storage compartment. Often, it's just the relay which goes bad. Good Luck.

[lepps]

I don't hear a thing when pushing the switch to put the driver's window down. Thanks for your expertise. I'll keep at it.

[gene2]

Search the SL forum for:
1991 300SL top controller & window relay
That may help, and also on my 1991 300SL I found that I must have a fully charged battery 12.6 volts for my windows to work properly.
If the 12.6 volts does not help. You just may need a new window switch.
I also had to clean my window switchs. As far as the window relays go, They may be in the controller, but they are not on the controller. Keep us posted.

[ctaylor738]

I would say that the diagnosis is accurate. The control unit refuses to send the appropriate "down" power and ground to the motor. It should power the window down when the window switch is pushed, and when you hold the button to lower the top. So it is failing at a single point with two different inputs. And it's confirmed by the fact that it works with a different control unit.

My advice is to get on car-part.com and look for recyclers that have the right year and model car by looking for an engine or trans or other common part. Then call them and see if they have the N52 control module. Be sure you have the correct part number.