[zdld17]

Guys, would any of you have a step by step wiper motor diagnostic method.

My wiper motor will not park blades when switch is moved to off position. I recall I dealt with this before and corrected it by replacing the wiper motor.

Long ago JimM sent me some steps to go thru but , that was long ago and I can't seem to find that sheet.

Wonder if anyone has such a method of correction , other than replacing one part at a time.
My wiper motor does have the ground strap as well as the wiper switch ground into the headlamp switch plate.

Any comments?

[KevinW]

I made up the test bench diagram in the electrical section quite some time ago, it will still be there Wiper motors get the 12v all the time and the switch actually controls the ground path. So with the switch turned on, the circuit is completed through the switches ground path. But when you turn the switch off, the ground path then moves over to the park circuit. The park circuit is controlled by a tab on an internal gear that keeps the motor grounded through the chassis (the wiper motor case is grounded via the brass ring on 1 of the grommets). When the tab reaches a certain point it opens the case ground, then the motor stops.

You need to make sure the case is trully grounded and not gummed up. If the ground is intact, then something when wrong with the internal grounding tab mech.

[zdld17]

Originally Posted by KevinW

I made up the test bench diagram in the electrical section quite some time ago, it will still be there Wiper motors get the 12v all the time and the switch actually controls the ground path. So with the switch turned on, the circuit is completed through the switches ground path. But when you turn the switch off, the ground path then moves over to the park circuit. The park circuit is controlled by a tab on an internal gear that keeps the motor grounded through the chassis (the wiper motor case is grounded via the brass ring on 1 of the grommets). When the tab reaches a certain point it opens the case ground, then the motor stops.

You need to make sure the case is trully grounded and not gummed up. If the ground is intact, then something when wrong with the internal grounding tab mech.

Thanks Kevin, the motor and switch is grounded and I did suspect the park tab.. but was not sure. I will dig into this for now. Been chasing this a long time when I remember to but in my area if forget about it as we only get about 12" rain, sometimes all in a few months.

[KevinW]

Here is what the inside of the wiper motor looks like. Its hard to see in that pic, but the tab is on the green gear in between the teeth and the shaft (around 9 o'clock). The park circuit contacts (2 sprung metal contacts) are to the left of the wound resistor. The tab on the green gear slide between the 2 contacts to break the ground to stop the motor.



Since we do not drive that much in the rain, you can always just turn the wipers off at the correct time

[zdld17]

Originally Posted by KevinW

Here is what the inside of the wiper motor looks like. Its hard to see in that pic, but the tab is on the green gear in between the teeth and the shaft (around 9 o'clock). The park circuit contacts (2 sprung metal contacts) are to the left of the wound resistor. The tab on the green gear slide between the 2 contacts to break the ground to stop the motor.



Since we do not drive that much in the rain, you can always just turn the wipers off at the correct time

Thanks again, The tab is what I suspect is the issue. Drive in the rain is normal when on PowerTours . Yes turning off that the correct instant is a trick, but when someone else other than myself drives, they don't know. I will use your old illustrations to check further but I suspect the tab is the problem, mabye too much grease on it?

[KevinW]

Hold on a bit... brain just got in gear (been sick since xmas )

do the wipers just stop when you put the switch to off? If so, then the park circuit ground is ALREADY broken. Its means the metal contacts are already apart or are not connected to the ground.

since your wipers work from the switch, the switch grounding is fine. I would take a wire from the neg battery and go directly to the case of the wiper (alligator clips work well) on an unpainted spot. And try the park again.

[zdld17]

Originally Posted by KevinW

Hold on a bit... brain just got in gear (been sick since xmas )

do the wipers just stop when you put the switch to off? If so, then the park circuit ground is ALREADY broken. Its means the metal contacts are already apart or are not connected to the ground.

since your wipers work from the switch, the switch grounding is fine. I would take a wire from the neg battery and go directly to the case of the wiper (alligator clips work well) on an unpainted spot. And try the park again.

What I was thinking also, Wipers do shut off from the switch but do not park. I will try your method later today or tonite. I have even added an additional ground wire from the motor to the chassis.
Get Well .

[click]

Don I just use Rain-X and forget the wipers as fast as you drive, water wont sit on your windshield at all

[zdld17]

Originally Posted by click

Don I just use Rain-X and forget the wipers as fast as you drive, water wont sit on your windshield at all

It works well except when stopped . I recall driving thru Iowa on one long haul, I never turned wipers on after I left from the stop until I got to a town lite.

I also recall MarkLW? coming from BC, with no wiper motor in the hole too. Fast car. Come to think of it, I don't recall any door glasses.
Rained on me all way from Billings to Dalhart, only used wipers to find gas stations .

[KevinW]

Originally Posted by click

Don I just use Rain-X and forget the wipers as fast as you drive, water wont sit on your windshield at all

But Rain-X and Wipers do NOT mix! the squeeking will drive you batty!

[click]

My windshield on my camaro or Tahoe never squeeked at all with both wipers and RainX , Maybe its the NJ smog?

[HwyStarJoe]

Must be because I've used RainX for years.

[KevinW]

Wouldn't doubt it

[HwyStarJoe]

Although, I drove through NJ quite a bit this past 6 months, a lot of it in the rain, and they still didn't squeak. Maybe you just need new blades Kevin!

[KevinW]

And you did not stop by and say hi?!?! sheesh