wiper motor testing

-

northeastmopar

FABO Gold Member
FABO Gold Member
Joined
Mar 10, 2010
Messages
776
Reaction score
52
Location
Massachusetts
Inked20200627_191517_LI.jpg
Just used my power probe. With the ignition key on and the NOS 2 speed wiper switch off, all terminals at the motor plug are dead. With the switch in low I get 11.4 volts at the terminal which plugs on the lower spade. With the switch in high, I get 11.4 volts at the terminal that plugs to the other spade. When I push the plug onto the motor, I get a motor that just sits there??? When I test the ground side, I get a green light on the mounting stud, the brass strap, and the motor housing?? SO, now how do I proceed without having to pull this motor as I do not really want to have to undo transmission arms. How do I test the motor in place?? I am sure I need to supply power to one terminal and ground another terminal correct. Oh, by the way, when I push the positive button on the power probe, it reads 12.4 volts and while pushing it I tried touching the 1 and 2 speed terminals on the motor thinking I was applying 12.4 volts there, but again, the motor did nothing??? Where to now???? View attachment 1715552200
20200627_191541.jpg
 
Last edited:
Mine didn't work I took it apart and the points were dirty. They are pretty simple , When reassembling it you'll install six new rivets three from the back and three from the front. The brushes lock back themselves you just have to push them after the commentator is in place. Make sure the armature is snap ringed in place then put the halves together. I have a bunch of 2 speed motors but mine had a 5/16 18 nut holding the linkage all the others I have are 1/4 20. I have more pictures of them apart if needed

DSCN0966.JPG


DSCN0967.JPG
 
View attachment 1715552636 I got to get this motor working to get a sticker. I got one of those power probes and here is a picture of my wiper motor. How do I go about testing this as it sits. I am not even sure I have the correct switch. This is a 2 speed wiper motor, right? It is what was on the car when I got it. View attachment 1715552200 View attachment 1715552201
Just used my power probe. With the ignition key on and the NOS 2 speed wiper switch off, all terminals at the motor plug are dead. With the switch in low I get 11.4 volts at the terminal which plugs on the lower spade. With the switch in high, I get 11.4 volts at the terminal that plugs to the other spade. When I push the plug onto the motor, I get a motor that just sits there??? When I test the ground side, I get a green light on the mounting stud, the brass strap, and the motor housing?? SO, now how do I proceed without having to pull this motor as I do not really want to have to undo transmission arms. How do I test the motor in place?? I am sure I need to supply power to one terminal and ground another terminal correct. Oh, by the way, when I push the positive button on the power probe, it reads 12.4 volts and while pushing it I tried touching the 1 and 2 speed terminals on the motor thinking I was applying 12.4 volts there, but again, the motor did nothing??? Where to now????
 
My only advice is download and read a few years of the service manuals at MyMopar. They have various test procedures in section 8. The "Passion for Mopars" website used to have some good info, but the "word here" is that the folks running that outfit are ??? falling down on the job
 
sounds like your open somewhere.
dc-motor-parts-6.jpg

should have continuity when you rotate to test each winding. Probably a bad brush.
 
It looks like you have a 72- A-body. Read the enclosed document to insure that you have the correct non reversing motor. Make sure all your grounds are good including the switch. These motors require good grounds otherwise they will do funny things. Follow the procedure and it should work. If not the grease on the inside may be rock hard and you would have to take it apart and clean it.
Any questions PM me
 

Attachments

  • wipertest.PDF
    347.2 KB · Views: 133
It looks like you have a 72- A-body. Read the enclosed document to insure that you have the correct non reversing motor. Make sure all your grounds are good including the switch. These motors require good grounds otherwise they will do funny things. Follow the procedure and it should work. If not the grease on the inside may be rock hard and you would have to take it apart and clean it.
Any questions PM me

Thanks but worth noting one of these is 2 speed, so when you download, rename the file
 
If you put 12 volts to the low Speed terminal the motor will run. If not you have a motor problem. Make sure your wiper pivots are not frozen. I test them this way all the time. Motor has to be grounded which it is when bolted to the car thru the thin brass strap.
 
Updated the document
It looks like you have a 72- A-body. Read the enclosed document to insure that you have the correct non reversing motor. Make sure all your grounds are good including the switch. These motors require good grounds otherwise they will do funny things. Follow the procedure and it should work. If not the grease on the inside may be rock hard and you would have to take it apart and clean it.
Any questions PM me
 

Attachments

  • wipertest.PDF
    347.2 KB · Views: 137
The 2sp motor is a permanent magnet motor the 3sp is a wound field
 
-
Back
Top