The last week my rear washer fluid pump has randomly turned on and won't turn off. I am thinking that there must be a short in the control on the steering wheel. Has anybody else ever had this problem?

Jeff

 

I have now realized that the short has to be outside the vehicle. It does it when the roads are wet or when I'm washing my vehicle.

I'm a little confused though. It seems that the power would only run out to the washer moter if the switch was on so if the wires near the motor shorted it wouldn't turn on because there is no power. This isn't the case. Anybody know how the wiring works and possible problems?

 

Well, if it's anything like the newer dome light (3rd gen runners and Tacomas up, at least) then it is an always hot device with the switch connected to the ground.

Sorry, only thing I can think of

EDIT:
If this is the case, maybe the water is seeping somewhere and completing the ground?
I don't know that much about electronics so...

 

WEIRD... Sorry no advice but here's a bump

 

On my '93 the washer pumps have power all the time and the switch completes the circuit to ground. If your's is the same then the short could be between the pump and the switch. Check for bad connections or broken insulation under the hood.

 

Your probably right. The ground must be showing somewhere so when the water hits , it grounds to the car and turns on.

I still have one problem. I forgot to say that if I turn the car off and then back on it quits, otherwise the pump will run until I turn the car off.

 

That means the short is on the load side of a relay somewhere. It de-energizes when you shut the ignition off and doesn't seal-in again until it reenergizes from manually turning it on or from shorting. You should be able to narrow down the culprit circuit by pulling fuses and relays to figure out which one it's fed from, then recreate the short and trace it from the fuse/relay box. Good luck! This type of problem can be a real headache!

 

There is probably a relay somewhere, when it gets turned on it stays on until power is interupted. On mine the rear wiper/washer is controlled by 5 or 6 relays in a module. I don't know what they all do but I'm guessing one of them turns on and supplies power to the rear washer when the window is closed. If that is the case try lowering the window, that might turn off the washer.
If not you'll have a really clean back window