Testing Windshield Wiper Motors

[Mav]

Decided to wait to post till I could come up with something that made sense, (forget the motor thing). Has been bad switch all along, just boxed up the 3rd new AAW switch and sent it back to Summit, they agree that if you get the same reading on continuity in the OFF position as the LOW spd. something is bad in switch. OER makes one for the 67 pickup, nobody knows what the difference might be, so they are sending one, will find out next week. If it works, hopefully I can make it fit.

[LockDoc]

Originally Posted by Mav

Decided to wait to post till I could come up with something that made sense, (forget the motor thing). Has been bad switch all along, just boxed up the 3rd new AAW switch and sent it back to Summit, they agree that if you get the same reading on continuity in the OFF position as the LOW spd. something is bad in switch. OER makes one for the 67 pickup, nobody knows what the difference might be, so they are sending one, will find out next week. If it works, hopefully I can make it fit.

Wow, who would have thunk it.... 3 bad ones???? Keep us posted.

LockDoc

[Mav]

If 67 switch wont fit/work, does anybody know if the Painless wiper switch has 3 terminals and if it will fit the OE plug? thanks.

[Mike_The_Grad]

Well MAV that is some luck you have with those switches. I'd buy a lotto ticket, all that bad luck has got to turn around sometime.
I worked with a guy a couple of years ago that would say, "If I didn't have bad luck, I wouldn't have any luck at all!" LOL.

[Mav]

Copy that! Yeah, they must have made a bad batch, but Im kinda getting tired of changing them, searching for an alternative....

[Mav]

This should be last post on this thread, you were right Lockdoc way back when you said it was wired wrong, but didnt know how or why until a fella from American Autowire showed me the correct way to test the switch and pointed out that not only was the Chevy schematic wrong on the location of the yellow wire, it also had the dk. blue and lt. blue reversed which has been the main problem all along. I dont know how they got reversed, I might have done it 25 yrs. ago when I changed washer pump, or was it wiper motor? Anyway, hopefully I have learned something....just glad to move on to next project.

[Mike_The_Grad]

Glad you finally got it resolved MAV. That AAW kit is the best investment I've put into my '72 C10.

[LockDoc]

Originally Posted by Mav

This should be last post on this thread, you were right Lockdoc way back when you said it was wired wrong, but didnt know how or why until a fella from American Autowire showed me the correct way to test the switch and pointed out that not only was the Chevy schematic wrong on the location of the yellow wire, it also had the dk. blue and lt. blue reversed which has been the main problem all along. I dont know how they got reversed, I might have done it 25 yrs. ago when I changed washer pump, or was it wiper motor? Anyway, hopefully I have learned something....just glad to move on to next project.

Wow, what an adventure..... but I enjoyed every minute of it. Not sure I can say the same for you. I think we all learn something when we encounter a problem like this.

LockDoc

[Mav]

Yes, pretty frustrating, but most of it due to me being in an area where Im not a bit confident in my abilities, (doesn't take much to be over my head w/electricity) but like you said that is how we learn. It would never have occurred to me to question a GM service manual, I know better now! Well thanks again you guys, maybe someday I can pass some of this on.....later Mav

[msg]

Hey Leon, Im trying out the bench testing on my 66 wiper motor and I am likely not understanding how to set the test up right.

Starting with the 1st test.

* Ground the wiper motor housing.
I took a black testing cable and connected the grounding bolt on the wiper motor housing to the dash cluster I had pulled figuring it was bare metal.


* Connect a jumper wire from a +12V source to the #2 (Power) terminal on the wiper motor. It's the bottom terminal on the rectangular motor or the middle terminal on the round motor.

I have a 12v A23 energizer battery that I was using as the source and connected the red testing cable to the #2 power terminal


* Connect a jumper wire from ground to the #1 (High) terminal on the wiper motor. It's the middle terminal on the rectangular motor or the bottom terminal on the round motor. This should operate the motor at high speed.

I connected a black testing cable to #1 High terminal and didnt understand how I should connect it to ground and be able to test the battery neg post to see if the motor operates at high speed. Where am I going wrong in the setup here?

[msg]

The only part I want to check on is the Ground. In the case of a loose battery is ground the neg post, or am I needing to get a separate ground wire? Or I guess pop the hood on one of our cars that are running and do this test? The truck is in pieces currently.

[LockDoc]

Originally Posted by msg

Thanks Leon for the detailed image! The only part I want to check on is the Ground. In the case of a loose battery is ground the neg post, or am I needing to get a separate ground wire? Or I guess pop the hood on one of our cars that are running and do this test? The truck is in pieces currently.

Yep, neg is ground. I would clamp a pair of vise grips lightly on the neg post and clip the wires to that

LockDoc

[LockDoc]

Originally Posted by msg

The battery was dead. So I went to the Honda and hooked things up. The test did cause the motor to spin, didnt seem like it was a high spin though. When I disconnected the black wire (the loose one in the pic) to ground the motor would run a sec and then go to the park mode.

That sounds good. Were you actually having trouble with the wipers or did you just want to test the motor?

LockDoc

[msg]

Originally Posted by LockDoc

That sounds good. Were you actually having trouble with the wipers or did you just want to test the motor?

LockDoc

Just wanted to test the motor, I havent re assembled my truck yet and before I went to the trouble of mounting everything up I wanted to know if the motor and pump worked. I think the high speed test shows its not working properly...or Im not testing it right.

[LockDoc]

Originally Posted by msg

Just wanted to test the motor, I havent re assembled my truck yet and before I went to the trouble of mounting everything up I wanted to know if the motor and pump worked. I think the high speed test shows its not working properly...or Im not testing it right.

I need to check and see if I have a 4 terminal motor.

LockDoc

[LockDoc]

-
OK, I told you wrong on the test. I knew I should have double checked before I posted that. I will delete my previous post and start over. I will post a condensed version of the instructions and a picture in the same post and maybe that will make it easier for both of us. The new picture has the terminals numbered to coinside with the instructions, see if that makes it easier. Remove all of your wires and start over....

Testing the wiper motor independent of the switch: (in or out of the vehicle)

The depressed park and non-depressed park 2-speed wiper motors can be bench tested independent of the dash switch by making the following connections:

* Ground the wiper motor housing. (to negative post on the battery)

* Connect a jumper wire from a +12V source (positive on the battery) to the #2 (Power) terminal on the wiper motor.

* Connect a jumper wire from ground (negative on the battery) to the #1 (High Speed) terminal on the wiper motor. This should operate the motor at high speed.

* Leaving the above connections in place, add an additional jumper wire between the #1 (High Speed) and #3 (Low Speed) terminals. This should operate the motor at low speed.

* Leave the jumper between terminals #1 and #3 but disconnect the motor from ground. That should cause the motor to run (at low speed) until it reaches its park position at which point it should stop.

If the motor operates normally in the above tests but not when installed on the vehicle then the problem is most likely in the switch or maybe the wiring. Also, the switch has to be grounded to the dash or the wiper will not work. Don't forget to check the fuse. The switch can be tested with an ohmmeter.

If the motor stops immediately when switched off (doesn't return to park position), first check the motor's ground strap. Since the motor is mounted on rubber cushions, it's grounded via a copper strap attached under one of the mounting screws. This is the ground for the park switch so the parking feature won't operate if the ground strap is missing, dirty, or corroded. If the ground strap checks out okay but the motor still doesn't go into park then the problem is most likely a worn out or dirty park switch. The park switch is located inside the motor's gearbox so some disassembly is required to check/clean the switch. I recommend consulting a good repair manual for the motor disassembly procedure.

See how that works.

LockDoc

[msg]

Thanks Leon! Too funny though I thought I loused up the high speed test and actually lucked up and had it going in high gear.

I re did the test and here is how it looked.

High speed test, spun high and parked after I disconnected the connection to the vice grip

[msg]

Then I added the jumper as instructed between #1 and #3 and it ran at low speed and parked itself after I disconnected the ground.

[LockDoc]

Originally Posted by msg

Then I added the jumper as instructed between #1 and #3 and it ran at low speed and parked itself after I disconnected the ground.

I deleted your last post. That test was for the round motor instead of the rectangular one. I changed the wording in the instructions also. The test you did in post #146 above would be the last test, when it was running on low speed and it parked when you removed the black wire from the vise grips. Your wiper motor is working as it should.

LockDoc

[msg]

Leon I really appreciate you helping me through, one last thing I have to replace now. Is the pump fairly easy to test? You may have already covered that in this thread, I will go and check. Thanks again!

[LockDoc]

Originally Posted by msg

Leon I really appreciate you helping me through, one last thing I have to replace now. Is the pump fairly easy to test? You may have already covered that in this thread, I will go and check. Thanks again!

Check out post #95 and see if that helps.

LockDoc

[msg]

Originally Posted by LockDoc

If you are going to replace the wiper motor anyway you could go ahead and put a kit in the pump. The thing to keep in mind is that anytime a vehicle has sat for a long time without the wipers/washers being used or a new kit is installed in the pump, the whole system has to be primed before the pump will pump any fluid. I use a turkey baster to prime the system while the pump is pumping. Also, while the system is apart blow through all of the hoses and squirter nozzles with an air hose. Do not blow air through the pump, you could rupture the diaphram in the pump. (and blow backwards through the squirter nozzles) Oh, and don't forget to clean the small strainer screen inside the washer tank.

If you decide to go with the external pump there are instructions on here for wiring it to the original wiper/washer switch.....

LockDoc

I dont mind replacing with a kit, but is it too difficult to test what I have now while its not installed on the truck? Currently the wiring harness hasnt been installed yet.

I watched this video on the replacement but this one is a 67 chevy van but its installed on the van while testing. The intro is creepy, but past that its informative.

https://www.youtube.com/watch?v=nUax433B3Bw

[msg]

Originally Posted by LockDoc

If you are going to replace the wiper motor anyway you could go ahead and put a kit in the pump. The thing to keep in mind is that anytime a vehicle has sat for a long time without the wipers/washers being used or a new kit is installed in the pump, the whole system has to be primed before the pump will pump any fluid. I use a turkey baster to prime the system while the pump is pumping. Also, while the system is apart blow through all of the hoses and squirter nozzles with an air hose. Do not blow air through the pump, you could rupture the diaphram in the pump. (and blow backwards through the squirter nozzles) Oh, and don't forget to clean the small strainer screen inside the washer tank.

If you decide to go with the external pump there are instructions on here for wiring it to the original wiper/washer switch.....

LockDoc

I checked out post 95 on testing the pump and I would like to try the kit replacement. I see you mention the turkey baster to prime it with which I will do. Question though, is there a similar way to test the pump with the jumper wires while I have it on the bench vs in the truck?

[ThreeQuarter]

Score another win for this 10yo thread. Helped me work through two mis-wired connectors and a poorly-grounded switch. Thanks Leon!

[sick472]

Yeah! Thanks Leon! This thread has helped me plenty along with the many others that you have contributed too.

There is a lot of Leon in my success.