Wiper 12v issue

ehiforgot

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Checked wiper motor and ground wirings all are performing properly. Fuse is good. Have narrowed issue down to power going to the motor. The hot side has zero voltage when key is on. Is there a relay I’m missing? 68 model year
 

melsg5

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No relays in that generation for wipers. The wires go to the bulkhead connector and then the fuse box.
 

ehiforgot

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So I was incorrect previously, the motor is getting voltage. I’m now fresh out of ideas for why the wipers refuse to work.
 

ehiforgot

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The wiring works fine when the motor is given 12v directly. Though through the wiring harness the wipers are dead.
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melsg5

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But you have no power at the motor so trace the wire to the bulkhead connection and if necessary disassemble the connector because the problem could be the connection between the two halfs.
 

ehiforgot

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But you have no power at the motor so trace the wire to the bulkhead connection and if necessary disassemble the connector because the problem could be the connection between the two halfs.
Little confused by what you mean by no power at the motor. Checked for voltage at the power lead and it read 12+ volts while the car was running with the wipers on.
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melsg5

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I find your posts confusing also. Post 1, no power at motor. Then post 3 and 4 you have power. What's different between direct and the wire harness? Bad plug?
 

ehiforgot

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So what i've discovered so far:
1) Wiper motor works
2) Wiper Switch works
3) grounds on wiring harness work
4) Motor is getting power from wiring harness.

When I try to turn on the wipers normally (with the wiring harness) nothing happens. As soon as I remove the power positive lead going to the wiper motor and connect the wiper motor directly to the battery everything works.
 

melsg5

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Do you have three wires on the connector?

Have you looked at a wiring diagram?

 

ehiforgot

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3 wires, Ive been trying to find a correct wiring diagram but unable to find the right one.
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cammerjeff

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I suspect you may have an issue with how well the wiper motor harness connects to the posts of the wiper motor. Try making a small jumper wires and connect them to the harness & Motor.

I suspect the harness connector is worn or corroded, when you check for voltage you make a better connection with the meter probe than the harness connector makes. Just an idea. Hard to tell without being in front of the car, or pictures.
 

ehiforgot

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I suspect you may have an issue with how well the wiper motor harness connects to the posts of the wiper motor. Try making a small jumper wires and connect them to the harness & Motor.

I suspect the harness connector is worn or corroded, when you check for voltage you make a better connection with the meter probe than the harness connector makes. Just an idea. Hard to tell without being in front of the car, or pictures.
I’ll try this

Also found correct wiring diagram, not sure where power wire goes from wiper motor to fuse block.
 

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ehiforgot

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Okay forgive me as I’m still learning. I was measuring the voltage at the wiper motor incorrectly. The wiper circuit is only getting 2v when key turned. This is the same for heater circuit but I don’t have a blower motor.
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NorCal65

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Okay forgive me as I’m still learning. I was measuring the voltage at the wiper motor incorrectly. The wiper circuit is only getting 2v when key turned. This is the same for heater circuit but I don’t have a blower motor.
And you have 12v at the harness?
I would agree with cammerjeff, check for corroded 12v wire or neutral wire at the connector.
 
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