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Window lift motor testing

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Good Morning,


How do you test the window lift motors (and other motors) to check that they are OK to put back in?


The motor is out and on my work bench - there are only two connection terminals and they check out OK for zero resistance - I put 12 volts from my bench supply across the terminals - there was a spark as the second terminal touched - the motor seemed to kick (slightly) as if wanting to turn, but didn't. Reversing the supply produced the same result. I cannot manually turn the shaft either. So, am I doing something wrong - am I doing something right but not enough - or does the motor need replacing




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I can only speak about the 1976 504 federal model but I have three wires on mine.  One is ground and the other two are up and down.  If you are getting 0 ohms across the leads I would think that is what you have there as well.


I might try checking between each wire and the body of the motor and see if you get some ohms.  I would guess 4 ohms or something like that but I didn't test mine when they were out.


Two wire motors are the norm now so maybe your car is newer and it has the two wire kind.  If you are getting no resistance across the two wires on the two wire kind it is likely a broken coil wire.

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On my 1979 car, and my 1978 replacement doors and the 1986 excel motors I kept as spares (which all seem to be identical) there are two connections wirth blade connectors and there is a black wire to ground mounted on one of the bolts which mount the motor to the door beam via a crimp washer.


I used jump leads off a battery,I put the ground on using the jump lead crocodile clip onto the door beam (or the body of the motor housing if its off), then put a bit of wire with a blade type connector onto one of the connectors.


as Ross says putting 12v on one connector to ground will turn the motor one way and vice versa. Don't connect across the two terminals! And make sure you only put 12v onto one of the connections at a time.


On my car some clever person had decided to spray the whole inside of the doors with underseal, resulting in gunged up slow motors but they still work. I've got photos of them somewhere. The motors on the replacement doors go much more quickly and smoothly.


Cheers, Mat.

Edited by mat grant

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Thanks to Mat
It worked
Here is the address to a photo of my set -up
Now, how to put it back together again?

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