dlister70

My windshield washer pump doesn't work, and I'm pretty sure it's the wiring. This is for a 1992 Toyota Pickup with a 22re if it matters..

I know nothing about electrical work, so this is probably going to sound ridiculous.. but here it goes.

I hooked up a dummy circuit tester to the negative battery terminal wire and touched it to the positive wire for the washer pump and turned the mist on, and the tester light came on. But when I hook the tester clamp to the negative wire for the washer pump and touched it to the positive wire, the light doesn't come on.

So I figure the negative wire isn't grounded properly and not knowing what I'm doing, I set about making a new ground wire for it. I just grounded a wire to the chassis and hooked that up to the pump. Now the pump works, but it's on all the time as soon as I turn on the car.

Clearly, I don't know what I'm doing (no electrical experience whatsoever, as if that isn't obvious).. but I'm sort of on the right track. What's the correct way to fix this? I see the wiring harness heads into the fuse box, and presumably the negative wire should be hooked to something in there?

Terrys87

iTrader: (1)

On my 88 build I have it listed how I got mine working, located on first post where to find it. The quickest way to see if the pump works is to pull the bottle and run a lead to each terminal to the leads on the pump.

My pump was frozen up and I switched polarity a couple of times and got it working. Still working great.

dlister70

I actually bought a new motor before I started messing with the wiring to see if it was just a bad motor.

I know that the motor works because after I ran the new ground wire the pump runs all the time (even with the wipers set to "off"). So the trick is.. how do I get it to only work when the "mist" is on? I'm assuming it has to do with running the ground from the chassis directly to the pump motor, but I don't know anything about wiring.

I did switch the negative and positive back and forth on the pump as I wasn't sure if I had them hooked up backwards. The motor ran continuously either way I tried it.. which didn't make any sense to me. I guess it doesn't matter which wire you hook to which terminal on the pump?

I went and looked at your '88 thread. There's lots of great info in there, thanks for the link!

Bad Karma

I have the same issue with my '91 pickup. According to the wiring diagram, the ground is applied through the switch, the +12 volts is always present at the washer motor, which is why it runs constantly when you ground out the wire. You (and I) need to find out where the ground signal is disappearing. I suspect mine is the switch on the column, I picked one up at the salvage yard, but haven't installed it yet...