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Does anyone have a diagram of the back of a wiper switch for a 1977 chevy monza. Mine doesn't work and I've hooked them up correctly on the firewall. The yellow wire was cut and someone put in a toggle switch to run them. Any ideas on why they wont work will help out.Thanks

All wiring diagrams are posted in the "best of" section of this forum
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The wires are arranged like this(I think)

1
2
3
4 5

1 = ground (originally a black wire)
2 = washer (originally a dark blue wire)
3 = unused slot in connector housing
4 = "LOW" (originally a black w/white stripe wire)
5 = "HIGH" (originally a light blue wire)

The wiper switch provides ground on both the black/white and light blue for low speed and only to the light blue for high. The yellow accessory+ does not go to the switch, but instead directly to the wiper(and washer) motors.
The usual reason for someone to put a toggle switch in the yellow wire is because the wiper motor "park" switch is defective and the motor runs constantly regardless of switch position as long as the key is on.

Spencer,The wiper motor has the yellow wire,the lt blue then the black with the white strip. Does it mean that the wiper with the motor in park all the time that the switch or motor is shot? Mine is just a 2 speed switch.

You will have to check the yellow wire at the motor for power and the others to see if they show ground with the switch in it's various positions.

I've checked for power at the switch and nothing from the yellow wire.. I did check for power with the other wires and nothing. I didn't check for ground though. I'll check for that tomorrow. What switch will work if it comes to that?

You won't find any power at the wiper switch; as I stated before, the power goes directly from the fuse box to the motor and the switch provides the ground. If you do not have power at the yellow on the motor with the key on, you have either a blown fuse or a broken wire.

Spencer,I took a peek and it was a blown fuse..They work now but won't shut off unless I turn the key off.So is it a bad switch or bad wiper motor?

Check the wiper motor case for ground. There should be a brass jumper on the mounting grommet nearest the 3 pin connector. The dash switch provides the ground for the motor windings when wiping, the body ground provides ground through the internal park switch in the wiper motor to allow the system to "park" the wipers at the bottom of their travel, after the switch has been turned off.

If the motor has ground, then the cause is burnt park switch contacts in the wiper motor assembly.

Well I took the motor out and took it apart,then put it back in and low and behold it works the correct way.Not sure if it was a ground issue or something inside the motor.Thanks guys

Yep, bad body ground at wiper switch. Your welcome eh.