Okay, so I am gutting all of the unnecessary crap from the wiring harness in my 1985 GS. I have removed all the emissions stuff, cruise control, factory stereo/amp garbage, power window wiring (not needed for my car), auto transmission, rear wiper (again not needed) etc. I'm basically doing a complete gutting of the wiring on the entire car. I've got the dash all the way out so I can get to anything I need. I have also removed the windshield washer reservoir and pump in the engine bay. As such, I am tracing back all of the wiring for it and pulling it out of the harness.

So here come the questions:

1) Do I need the highlighted blue and yellow wires or can I remove them? Here is my thought, I don't have the washer motor anymore so removing the wires between the combination switch and CPU aren't going to matter. All the LY wire does is cause the washer motor to shoot washer fluid and then cycle the wipers on a timer for a few seconds (controlled by the CPU). So removing the LY wiring isn't going to affect the normal operation of my wipers at all, correct? All it would do is keep the wipers from wiping if I were to pull the stalk towards me?

2) What is the function of the blue wire that goes into the CPU and branches off to the wiper motor? I left it there b/c by my understanding it is necessary for the wipers to work correctly, however can someone explain to me what is happening there?

Can someone smarter than me confirm? Mostly question #1, question #2 is just for my own understanding. Thanks in advance. Wiring is not my strongest area, in fact it's probably my weakest...

 

Looks to me like the blue wire into the wiper motor is primary power for the motor, Jaime. If you remove it your wipers will not work.

Blue wire from the fuse is powering washer motor, the CPU timer AND the wiper motor.

The yellow wire is ground for the washer motor (which you're removed) and for the coil of the CPU's internal relay that activates the wiper when you run the washers.

If you want to verify that the yellow wire is unnecessary, unplug the CPU from X-11. Since you've already removed the washer motor, that will completely isolate the yellow wire. If the wipers work the way you want with the CPU unplugged, then the yellow wire is unneeded.

But you need the blue wire to connect from the fuse to the wiper motor.

They're switching via the ground sides here instead of the positives, which looks odd but works just fine, and probably saved hundreds of thousands of feet of wire over the entire production run.

 

Okay, thats exactly what i thought when i was looking at it. I removed the blue power wire for the washer motor back to where it splits to the cpu amd wipers, so they should still have power comimg in. Im going to pull out the blue and yellow wire all the way back to the switch but wanted to get a second set of eyes on it first. Sounds like the wipers should still function normally otherwise.

 

https://www.rx7club.com/1st-generati...iring-1082294/

Funny you should mention it, I went through wiper wiring on my race car a little while ago. The solid blue wire has power all the time, all of the switching is with grounds, either through the switch, control module, or the park switch on the gear.

 

my 1980 is giving me fits, the wipers never are "off" but the off setting only yields the low intermittent setting. #saproblems

 

That's most likely either a short, or a combo switch issue, GM.

1980 wiper wiring is considerably different from the above. Simpler, but different.