Merc sports wiper.

[jetblack]

my wiper on my 129 sports will only work on the fast speed, speeds 1 & 2 dont work, everything else is O.K. any ideas, thanks.

 

[Dec]

Two possibilities, the wiper switch at the stalk or the motor.

It might be worth opening the end of the stalk to investigate, it is not easy to spot any faults inside the switch as it is mostly enclosed, however operating the wiper with the switch in its dismantled state may give some clue as to the fault.

The second possibility is that the resistor inside the motor or the wiring to it is at fault, I don’t know too much about this “resistor” but it has something to do with how the speed of the motor is determined.
As I understand it, the wiper motor really has only one speed, which is fast, so that when the switch is in position 3, power goes directly to the motor, and you get fast speed.
In position 2 or position 1 (intermittent) power is fed through the resistor.
The resistor absorbs some of the power and so slows the motor down to “normal speed”, (intermittent is normal speed, but with an interruptions every 6 or 7 seconds by the relay)

I have a hunch, because you only have fast speed and no other fault, that it is something to do with the resistor (if indeed that is the correct name for it) inside the motor. If that were the case you would have to replace the motor, as I doubt that it could be repaired.

Links below, are for a C Class W202, am not familiar with your car but yours should be similar to this.

Stalk switch pictures… http://forums.mercedesclub.org.uk/showthread.php?t=38617
Resistor is red box in first picture of post #17… http://forums.mercedesclub.org.uk/showthread.php?t=37082&page=2

Dec