Wiring single speed wiper motor

[Aaronoregon]

So.......... I thought this would be easy! My motor only has two prongs on it total so is just a single speed motor. I am not running a washer pump. The switch I have is a three prong. I ohmed it and the two outer prongs have continuity when you turn the switch. I assume the center is for a second speed or a washer pump?

I originally thought I just wired the fused 12v through the switch to one of the prongs on the motor and grounded the other prong on the motor. This worked great when it was hanging to test it, but as soon as I mounted the switch it started blowing fuses. I assume because the case was grounding to the dash?

At this point, I sent the fused 12v straight to the motor and then off of the other prong grounded it through the switch. Blades ran a pass and parked. How the hell do I wire this?

I'm thinking it parks when grounded, but what do I need to do to make this work? Thanks guys. Below are pictures of what I have.

[ray_mcavoy]

Yes, as you have discovered, the switch is case ground and is intended to be installed on the ground side of the circuit. And yes, that 3 terminal switch is meant for a 2-speed motor with washer but can still be used on your single speed motor.

Your 2nd attempt at hooking up the switch sounds like it was correct ...send fused 12V to the motor's power terminal and ground the motor's other terminal (through the switch) to make it run.

The parking switch is internal to the motor's gearbox and is wired internally to the motor. The fact that your wipers made a single pass and then parked sounds like your dash switch only made a momentary contact ... enough to start the wipe cycle and then the park switch took over to finish the cycle.

With the 3 terminal switch, you'll probably want to make use of the "high" speed terminal to run your single speed motor. That "high" speed terminal should be connected to the switch case when the switch is in either the "low" or "high" position. And it will be open from the case when in the off position.

[Aaronoregon]

The switch may not be grounded good through the dash. Are all three prongs grounded to the case on the switch? Thank you.

[ray_mcavoy]

Yeah, make sure the body of the switch is making good electrical contact with the metal dash.

Yes, all 3 of the terminals get grounded via the switch case for the various functions. When the switch is in the "off" position there will be continuity between the "high" & "low" terminals but they will both be open from ground (switch case). When the knob is turned to the "low" position, the "high" and "low" terminals remain connected together and also get grounded via the switch body. Then when the knob is turned to the "high" position, only the "high" terminal is connected to the switch body. The "wash" terminal is momentarily grounded when the button in the center is pushed in.

[Aaronoregon]

I got it. Threw me for a while, but it worked out. Thanks guys!