Does anyone have good wiring diagrams for the wiper motors?

[kipps]

I'm not simply looking for pinouts, i.e., connect this pin to that pin, etc. Rather, I want an actual diagram that shows what's happening so I can understand it. I've been searching for while, and drawing a complete blank.

Everybody is speculating about how they work, but nobody can produce a definitive diagram showing what's happening. Please help!

My truck is a 1987, wiper switch on the stalk, and was originally equipped with intermittent wipers(based on the rpo code). I don't think I have the control box anymore, but that can be procured from a junkyard.

[kipps]

Actually, I re-checked the factory manual, and found a reasonable diagram. Section D, Page 78-ish in the 1988 wiring manual.

[hatzie]

The 88 & 89 wiring diagrams are generally easier to follow than the 87 diagrams.

The wiper switch is on the ground side of the motor. There are no power wires running from the switch to the motor... just grounds.
EDIT** The wiper motor has fused ignition power in one or two places on the motor. The washer (on the pre-83 systems) and the motor directly from the fuse block.
The park switch closes contacts from the wiper OFF connection to the motor to the LO windings and opens contacts when the wipers are in the park position.
The wiper switch closes contacts to ground. Off to the park switch, Lo to the Low motor, and Hi to the High motor.
The pulse module has three additional wires from the column switch. These wires run from all three legs of a potentiometer in the switch to the pulse controller. The pulse module grounds the output to the LO motor windings.

[kipps]

Okay, now I'm really confused. What's the chances the diagrams on page 78 and 79 have gross errors?

Just to start with, what's happening inside that park switch? My logic says there's no power going through it; only ground. Based on the diagrams, one wire gets spliced over to the slow speed motor ground. The other wire goes back to the column switch.

Your description of the operation made the most sense. Both p.78 and p.79 make no sense in their portrayal of the column switch.

[hatzie]

Originally Posted by kipps

Okay, now I'm really confused. What's the chances the diagrams on page 78 and 79 have gross errors?

Just to start with, what's happening inside that park switch? My logic says there's no power going through it; only ground. Based on the diagrams, one wire gets spliced over to the slow speed motor ground. The other wire goes back to the column switch.

Your description of the operation made the most sense. Both p.78 and p.79 make no sense in their portrayal of the column switch.

I was posting that from memory and I screwed up.
You are correct the park switch is grounded from the OFF switch position. I'll edit my post to correct that.
The power wires run to the motor and the motor mounted washer.