Found several messages on older wiper problems, but nothing pertaining to my Van. My wipers will sometimes work correctly for less than a minute, but then they will take off on constant lo speed, even if the switch is turned to the OFF Position!!! (hi position works correctly). This created quite a distraction, as you would have to pull over and shut off the engine in order to get the wipers to stop. So I installed a cutoff switch on the wire going to the wiper motor so that we could kill the possessed wipers at any given time.

The wipers are controlled by a combination turn signal/wiper switch on the column. Resistors embedded in the end of the turn signal arm control whether the wipers are delay, lo, or high. At the bottom of the dash, above the accelerator pedal, is the Wiper Control Module, the relays and electronics which interpret the electrical signals from the turn signal/wiper switch. From there, power is sent to the wiper motor.

I went to a scrap yard and picked up another Wiper Control Module. However, this did not correct the problem. I took apart the wiper switch and cleaned the contacts, but still the problem persists. The symptoms would make me believe that this is more of an electronic problem rather than a switch problem.

I saw in some previous messages suggestions to check the grounding wires. That is probably a good idea and I will look into it.

Any other ideas are welcome. I am hesitant to go lay down $45 for a new combination switch, as I am not 100% convinced that is the problem.

 

More on what I have found about wiper problem:
The grounding wires were OK, so I started checking into possible shorts in the ground, looking for a positive voltage between the body and the negative terminal on the battery. No problem there.

However, in the process, I discovered that the wipers only go bezerk when the engine is actually running. If the engine is off, the wipers work correctly.

I am now looking into possible alternator or voltage regulator problems.

Any other ideas are welcome.

 

I have no idea what is causing this problem. I eventually broke down and bought NEW Ford parts: Wiper Control Module @ $71 and when this did not correct the problem, a new Turn Signal/Wiper Switch @ $72. Believe it or not, the problem is still there.

I note a rash of similar wipers problems posted recently. Does anyone have the answer as to why the wipers run continuously (even in the "off" position) with the motor running, but work OK when the engine is off??

I think I now need to schedule a visit to Ye Ol' Ford Dealer.

 

Finally solved the problem. Wiper Motor. For full summary of experience, see the thread "Wiper Problem$?? Read Thi$!!!