1991 Wipers!

Pogiefish

New Member
Apr 17, 2013
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I changed fuse, motor, multiswitch and govenor. Still nothing. I have power going to the motor. I also hear noise coming from box in front of center console. Any pointers?
 
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Pulled motor again. With the 2 plugs connected, I can get the motor to turn on by handstarting it. But, when I try to change speeds or turn it off, the motor will shut off and will not start by itself.
 
Check the voltage with the motor running. It should be the same as battery voltage minus .25 volts or less.


The wiper motor does not have a resistor pack inside it. It does have one armature brush offset from the other two and a cylindrical permanent magnet instead of a set of field coils. The two brushes directly opposite each other are the low speed brushes. The low speed brush works in conjunction with one of the high speed brushes to provide a second speed.

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Self Parking mechanism:
The self parking mechanism is copper circle glued or stuck on the wiper gear. The circle always has 12 volts on it until the wiper comes to the park position. There are two copper spring switch contacts, one provides power to the copper circle, while the other provides a path to the low speed winding. The power contact always provides power to the copper circle except when in the park position. The low speed contact is always in contact with the copper circle. When power is turned off at the wiper control, the 12 volts continues to flow to the low speed motor brush until the wiper blade returns to the park position.

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Interval Governor:
The interval governor is a fancy electronic switch that sends the motor a pulse of electricity that varies in duration time. It always runs on the slow speed motor brushes. Turn the wipers on and quickly turn them off. The self parking mechanism inside the motor makes sure that the wiper blades come back to the park position and stop there. The interval governor does the same thing: it sends power to the wiper motor and then turns it off. The duration of the pulse sent to the motor determines how many strokes it makes before stopping at the park position. If you watch carefully, you will notice the wiper blade speed is constant and never changes when you are using the interval wiper function.

Troubleshooting:
All tests done with the ignition switch in Run or Accessory position and wipers on.

1.) Look for constant 12 volts on the red wire on the wiper motor. No 12 volts, the fuse is blown, bad wiring or bad connection. This will cause park problems or no wiper operation
2.) Check the ground. No ground and nothing works, bad ground and you get intermittent operation.
3.) No high speed operation, low speed OK. Look for 12 volts on the Dark Brown/orange wire. No 12 volts, bad wiper switch, bad connections or bad wiring.
4.) No low speed operation, high speed OK. Look for 12 volts on the white wire. No 12 volts, interval governor faulty or missing, or bad wiring. Since this is a pulse and not a steady voltage, a test light used in parallel with the voltmeter may be a better indication of operation
5.) Motor low speed test: Jumper the brown/white wire on the interval governor to the white wire. The motor should run in low speed mode. I haven’t tested this yet, so use caution. If the motor does not run, the low speed brush may be bad.

Do all this and by that time, maybe I’ll have figured out some simple tests for the interval governor…

See http://www.popularmechanics.com/cars/how-to/maintenance/how-to-fix-your-windshield-wiper-motors-2 for more help.
 
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Got it! Thanks for schematics. Wrong wire to wrong pin. I got this Mustang from a 72 year old man who hand the steering column out off car. Needless to say what happen. He sold the car because he said he was to old to fix it. Thanks guys for all the help.