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Wiper Motor Voltage

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Jim_Gruber

Jim_Gruber

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Just tried to flip on the wipers this evening only to find they weren't working. Voltage measured at the plug going into the wipers is 1 & 2 volts respectively hi/lo setting. I'm sure I've got either a crappy ground or a case of green terminals inside the wiper switch contacts. Can anyone confirm voltage readings for the wiper motor.
 
Jim

Were the wires connected or disconnected?

Pat
 
Disconnected. Measured voltages at the plug. Took a couple of paper clips and pushed into connector and measured with VOM. Key in run position, wipers on low and high 1 & 2 volts respectively. I don't know of any type of ballast resistor that lowers voltage going to the wiper motor,
 
I really don't think there is anything like a ballast resistor. Even if there were, you still should measure 12V with the connector disconnected. I'd trace back through the circuit and find where there's a bad connection. Almost certainly that's the problem. Maybe the switch itself.
 
Thanks,

I'll dig out the wiring diagram but I'll bet when I take the wiper switch apart it will be all green on the connections.
 
Finally figured out my wiper voltage issue. I had replaced the speedo recently and the ground wire that feeds the wiper is tied into the knurled nut on the back of the speedo with a ring eye. I had tightened the knurled knob with my hand up behind the dash and did not inspect it visually. There must be a buggered up thread on the back of the speedo housing as I discovered all of the ground wires sort of hanging loose and the knob tight but tight against a buggered up thread. I still had more than 1/4" to get it tight. Very long needle nose pliers allowed my to get the knob past the buggered up thread section and everything is now tight. Wipers and Washers now work again. I'm guessing that buggered up section of screw might have been caused by an idle spark as the ground wire was not screwed down tightly. A potential disaster averted.
 
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