How to Test a Single Post DC Motor

Dec 12th 2017

How to Test a Single Post DC Motor

This test will work for any 12 volt, single post, DC motor. Before you test your motor, you will need to remove it from the vehicle.

What You Will Need

Battery Jumper Cables
Working Battery (Take one from a working vehicle if possible. Battery must have 12.5 volts. DO NOT use a jump box)
Vise to Hold Motor (You can have someone hold the motor if you don’t have a vise)

Bench Testing

Before you test your DC motor, you will need to remove it from the vehicle.

Step One: Place your motor in the vise or have someone hold it carefully.

This test only applies to single post DC motors.

Step Two: Attach the negative (BLACK) battery cable to the to the negative terminal of the battery. The other end will need to be attached to the motor case.

After you've connected the negative and positive cables and the DC motor does not spin, it means that your DC motor has given up the ghost.

Step Three: Attach the positive (RED) battery cable to the positive terminal on the battery. Touch the other end to the post. As soon as you touch the battery cable to the post, the motor should start to spin. If the motor fails to spin, then it is defective and needs to be replaced.