[RocktimusPryme]

I dont drive in the rain much, but if I get caught I want my wipers to work.

I had working, but kinda weak wipers. Meaning they would have trouble sliding across a dry windsheild.

It seemed to get worse, so I decided to buy a new motor. I rock autoed one. It doesnt have the spiral gear on the front for the washer motor but thats a different story.

Anyway, installed the new unit and it wouldnt work. I thought it was a ground issue, since the screw that has the brass piece on it is broken off in the firewall so I cant use that screw hole. Motor is only attached with upper and driver side screws. However, when I jumped the ground, it still didnt work.

So in a nutshell here is what it will and wont do.

1. Will not turn on wipers with switch.
2. If you have the wipers out of park alignment and turn on the key, they will return to park mode.
3. I discovered if you push the switch in (which I think should be the wash spray button) then the wipers work.

So now Im starting to think its not the motor, but the switch. What say you guys.

[ELKHORNAOG7]

it sounds like the switch ,you should take a jumper wire and unplug plug from back of switch and feed power to motor at plug and see if t works then also take test light and see if you have power thru wire when switch is turned on also check the fuse and see if it is good-------BOB

[tinindian68]

I had the same issue and the switch had an intermittent ground. Try running a good dedicated ground wire to the switch as well.

[RocktimusPryme]

Originally Posted by tinindian68

I had the same issue and the switch had an intermittent ground. Try running a good dedicated ground wire to the switch as well.

A good point. Ill have to figure out which post on the switch is the ground.

[RocktimusPryme]

Originally Posted by ELKHORNAOG7

it sounds like the switch ,you should take a jumper wire and unplug plug from back of switch and feed power to motor at plug and see if t works then also take test light and see if you have power thru wire when switch is turned on also check the fuse and see if it is good-------BOB

I have power to the posts on the motor itself. I kinda thought the switch must be providing ground instead of power. Because it seemed like no matter if high or low all the posts on the motor itself light up the test light.

[Bill Hanlon]

The wiper switch does supply all grounds for the motor. The motor has 12v all the time.

[RocktimusPryme]

Originally Posted by Bill Hanlon

The wiper switch does supply all grounds for the motor. The motor has 12v all the time.

So if I’m getting power to the motor would you agree that the switch is my likely culprit?

[Bill Hanlon]

Originally Posted by RocktimusPryme

So if I’m getting power to the motor would you agree that the switch is my likely culprit?

Likely, but not 100%. Could be that the switch isn't grounded.

JohnTA1 posted two very helpful drawings in posts 17 and 18 of this thread.

https://forums.maxperformanceinc.com...d.php?t=844278

I don't know what year his drawing is from, but it should be generic enough to get a good idea how the wipers work.

[Bill Hanlon]

Originally Posted by Bill Hanlon

The motor has 12v all the time.

I should have said "The motor has 12v all the time the key is in run or acc".

["QUICK-SILVER"]

Un-plug the wiper motor and probe the terminals in the connector with a test light hooked to B+.

Don't know correct locations but it takes two terminals grounded for low speed and one terminal grounded for high speed.

Once you identify low/high from the switch you can use a jumper to ground and test the wiper motor.

Key off for switch testing and key on for motor testing

Clay

[RocktimusPryme]

Thanks guys. Im confident its not the motor. I have the original motor and new motor doing the same things. So unlikely the motor itself is at fault. It could be the motor case not grounding, but I feel like Ive tested that.

That leaves the switch itself or the switch ground.

Does the switch itself ground via the case to the dash? I found this picture of a 67 corvette switch which is probably similar.


At this point I just have to talk myself into removing the gauges. Thats the only easy way to get to the switch.

[OG68]

From the 68 Diagnosis manual

[RocktimusPryme]

So idk what this means for any grounds, but with the new motor in and the engine actually RUNNING the wipers work fine now.

Previously I had only been testing with the key in the ON position but with the engine off.

While it’s probably still not dead correct, it appears to be at least functional.