Hello to everybody...I'm new to this forum. Got a 93 400sel for about 2 years now and love it. It's not perfect, there's some hidden problems that some I already fix and others is just I can't figure it out. Things that I already done was replacing the accumulators,central vacuum pump and signal light relay. I'm still having a problem with my wiper. Once you turn it on it will not go off and it has only 1 speed. You need to turn off the ignition switch to turn it off and waited for about 5-10 minutes before turning back on the ignition switch, if not the wiper will still be working. I'm thingking that the switch is bad but not really sure. Tried to replaced with a new wiper module but still the same effect. The other thing is my battery is draining out if you don't use the car for about 5 days. Can anyone have any idea to deal this kind of problem???Thank you in advance....

 

if it's the switch, the problem should be there all the time either you turn the ignition on or off.

aside from the combination relay (turn signal, heated rear window, wiper motor), you also got wiper system relay module. best way to find if they are defective is to install a good one for checking purpose.

the motor also got return sequence contact inside which it is constantly supplied with voltage until the wiper blade is in park position.

welcome to the forum.

 

Thanks for the info. sleepwalker..I haven't tried to look at the wiper switch. I did replace the wiper module near the engine compartment and still doing the same thing, that's why I suspected the switch. I forgot to tell that the headlight wiper is not functioning also. Are they inter-connected? And Since this is my first Mercedes Benz I don't want to open up everything, not unlike the japanese or american cars. When I got the car, I did not know that the electrical system of german engineering is a little bit complicated, especially if you do not have the wiring diagram and the procedure on how to find and get to the switches or relays of the car..but some how with the help of the forum I manage to do and fixed some of the trouble like the accumulators,central vacuum pump and the signal light relay...The phone system is not functioning also..no power at all, I don't know where's the relay/switch are located? Is this why my battery is draining so much if I don't use it for a week....Thanks again....

 

the headlamp wiper got it's own relay then goes to that combination switch. i suspect the motor is seized so better start from there.

you will also know if the switch is bad because it got a different feeling on it (binding, noise, rough or loose).

your battery drain, follow the procedures posted here before. they got many ways to do it using the ammeter. maybe you got weak battery too.

 

Thanks again and I'll try to do that....I'll get in touch with you later.....