Wiper motor wiring

I'm trying to get the wipers to work so I can pass a vehicle inspection here in NC. There are 3 wires coming out of the motor, green, black and red. The PO clipped off the black and red. There is also what I assume to be a ground wire hanging off the mounting screw. I am just trying to get the motor to work. I've got a hot lead coming off my EZ21 fusebox to the wipers. Does that get connected to the green wire as the PO did? And what about a ground, is the wire from the mounting screw sufficient? Doesn't work that way so I'm hoping it is a wiring issue not a motor issue. Thanks,

Milan

 

Sounds like a 2-speed motor with park. Ground is probably through the case of the motor, so the wire coming off the mounting screw was probably the ground lead. I like to run a dedicated ground for wiper motors.

One of the 3 other wires will probably be for low speed, one for high speed, and one to "park" the motor. If this is the case, your wiper switch will feed +12V to either the low or the high terminals. The park terminal will be fed +12V all the time. What happens is if you turn the wipers "off," the live park feed will run the motor until it gets to the "parked" position and it will then stop. I can't tell you which one is which though. Best to use a meter to try and get an idea of which one is which, or you may have to take the motor apart to see which is which.

Stan

 

i will look tongiht when i get home, but you can just use trail and error to see which one is for high and which is for low

 

i bought an after market wiper for mine and i couldnt get it to work for nothing.i took it back to the store and the guys there fiddled with it untill we discovered that i had to switch the ground wire. i was switching the hot and it wouldnt work. maby something to watch for.

 

There's a discussion of the two speed wiper operation in the '72 TSM. You can (slowly) download the chapter from C104.net. Basically, you need one hot wire, one ground, and a combination of the remaining two wires to ground. Look at the TSM. This topic has also been discussed recently on the ECJ5 V6 forum, so look there too.

 

used the trial and error method when i converted to the later single motor w/top wipers. I also ran a 4th wire to use as a ground. another tip is to get a 4flat trailer plug connect the wires to the jeep, works real well if you need to take the windshield off.