Windshield wiper problem

Maintenance/Repairs
1

I have a 1985 Mercedes 300 Turbo diesel wagon, for some time the windshield wipers have started operation without the switch being turned on. A Mercedes service station thought the windshield wiper switch to be shorting, and the wiper switch was replaced. That didn’t fix the problem, it seems to have something to do with heat. In cold temp. seasons the vehicle can be driven in excess of a hundred miles before the wipers start up. In warm temp., the vehicle may only go fifteen to twenty miles and the wipers start. I’ve had several service operations look for the problem, but they haven’t been able to locate the cause. I’ve been told to wait till the wipers cease to function so they can locate the problem, that’s dangerous, as we travel cross country and could get caught without the use of wipers in a remote area. Any suggestions>

2

Look For A W/Wiper Relay. See If There Is Another Relay With The Same Part # (Non-Essential For The Car To Run) And Swap Them, Temporarily. It Could Be A Bad Relay.

CSA

3

I believe CSA is correct, but I will add one more thin for the list. There is a switch inside the motor that allows the motor to run after you turn the wipers off, until it is in the park position. That “switch” could be the problem.

Do as CSA suggest first as it is cheap (free) and easy to test.

4

Along with JEM I tend to think it is the PARK switch inside the motor that is the trouble. Checking for voltage on the lead that ties to the motor from the switch while the trouble is occuring would verify if there is a problem on the switch lead or not.

5

Many thanks for your quick reply, not being auto mechanic inclined I’ll take your suggestion to my independent mechanic. Whatever the solution, I’ll report.

Again, thanks

Storbantiq

6

Hi, as I responded to CSA, appreciate your quick reply, not being auto mechanic inclined I’ll take suggestions to my independent mechanic. Whatever the solution, I’ll report.

Thanks,

Storbantiq

7

Hi, as I responded to CSA, appreciate your quick reply, not being auto mechanic inclined I’ll take suggestions to my independent mechanic. Whatever the solution, I’ll report.

Thanks,

Storbantiq