Testing Power Window Motors

[kdml]

I have all of the window regulators and motors removed from my '65.  They were all removed when I purchased the car.  I have disassembled and cleaned out all of the old grease from the motor.  The spin freely by hand.  I would like to test the motors before reinstalling.  I assumed I could connect to a car battery and they should operate, but it is not working.  There are two connections on the motor.   Is there a proper order to connect?  Do I connect both to the battery or one to ground?  

 

Thanks

Doug

 

 

[RivNut]

Two terminals. One for up, one for down.  Ground is through the case.

[RockinRiviDad]

Most will use a 12v drill battery

[68RIVGS]

As Ed stated, one terminal for up, and  the other for down.

The chassis ground is usually through the case via the mounting bolts.

You can use any +12V DC source to test the motors.

Edited November 19, 2018 by 68RIVGS (see edit history)

[Barney Eaton]

If you have a battery charger that is an excellent unit to use for test power.

[telriv]

Use a 12 volt battery , a jumper box or some kind of source for 12 volts that has enough amperage to operate the motor. AT LEAST 10 amps. Use two jumper wires. Connect both jumper wires to the 12 volt source. One to negative the other to positive. One jumper wire goes to one terminal. The other jumper wire goes to the other terminal. Just don't let the jumper wires touch together. Wrap one of the jumpers leads in tape to help prevent shorting. The motor will now go one way. Reverse the connections & the motor will spin the other way. The motor DOES NOT ground through the case. It reverses direction at the motor through the jumper wires NOT through a ground to the vehicle so the motor DOES NOT have to be grounded.

Let it run for a while in both directions to see if it still operates. Since there is NO LOAD against it/it will run for hours WITHOUT any harm.

 

Tom T.

[jsgun]

I think you're thinking of the later reversing motors. My motors had to be case ground to the negative power source. The positive wire goes to one terminal. Be sure to test both terminals, I had a motor that turned one direction great, the other direction barely. Once mine were cleaned, they pulled a solid 17 amps freewheeling. Crazy powerful motors, use at least 12 gauge wire for testing to get enough juice to them.

[kdml]

Thanks all

 

Jumping to both terminals didn’t work. That is how I started. Running a wire from the negative battery terminal to the case and a wire from the positive terminal to one of the terminals on the motor worked. Switching to the other terminal on the motor worked in the other direction. 

[telriv]

I needed to get the widows down on a '66 Wildcat in a salvage yard to gain access to other parts & the way I explained it is the only way it worked for me using a jumper box.

This has been my experience in the past also on the older cars. Not only GM but Ford & Chrysler also.

[68RIVGS]

23 hours ago, telriv said:

Use a 12 volt battery , a jumper box or some kind of source for 12 volts that has enough amperage to operate the motor. AT LEAST 10 amps. Use two jumper wires. Connect both jumper wires to the 12 volt source. One to negative the other to positive. One jumper wire goes to one terminal. The other jumper wire goes to the other terminal. Just don't let the jumper wires touch together. Wrap one of the jumpers leads in tape to help prevent shorting. The motor will now go one way. Reverse the connections & the motor will spin the other way. The motor DOES NOT ground through the case. It reverses direction at the motor through the jumper wires NOT through a ground to the vehicle so the motor DOES NOT have to be grounded.

Let it run for a while in both directions to see if it still operates. Since there is NO LOAD against it/it will run for hours WITHOUT any harm.

 

Tom T.

 

??????????????????????????????????????????? HUH?.

Have a gander at a schematic Tom - all power window motors are chassis grounded by the mounting bolts.

Each 3 wire power window switch is powered +12VDC,  and the other two motor leads are up, or down.

The power window motors are grounded via the motor mounting bolts !

Edited November 20, 2018 by 68RIVGS (see edit history)

[65VerdeGS]

On 11/18/2018 at 9:47 PM, Barney Eaton said:

If you have a battery charger that is an excellent unit to use for test power.

 

Hi Barney - good idea to use a battery charger.  Would I put the charger on ‘fast charge’ mode to use it to provide 12v to a window motor being tested?

 

 

[Barney Eaton]

Try it first on the slow charge setting.........that may limit the amps the charger puts out.......if the motor does not work at that setting switch to he fast charge setting and test.

Your charger will probably have a meter......when you get the motor running,  the meter will give you an indication of the current/amp draw.

Car electrical was pretty simple before they went "electronic".    If the motor works on the bench but not in the car,  check for a good ground.

 

This photo is a 1987 GM power antenna motor that died by meltdown..... don't know if it overheated or shorted, but it got pretty hot.

Edited November 20, 2018 by Barney Eaton (see edit history)