Motor Current Draw Test

Fig. 1 Wiper Motor Current Draw Test:

CAUTION: Electric wiper motors contain permanent magnets made of ceramic. This is a hard glass-like material that can shatter or crack if the motor receives a severe physical shock. Do not handle any windshield wiper motor abusively when diagnosing wiper operations, because it will damage the magnets and make the motor inoperative. Rough handling of new replacement motors may also damage the magnets.

NOTE: The windshield wiper motor tests can be performed with the wiper motor installed in the vehicle (linkage disconnected), or on the bench.

1. Disconnect positive cable from battery.
2. Disconnect wiper linkage from wiper motor.
3. Disconnect electrical plug to test motor on vehicle.
4. Connect the green lead from the tester to the battery positive post.
5. Connect the positive (red) lead from the tester first to the low-speed connection and then to the high-speed connection at the connector plug. In either case, the current draw should not exceed 3.5 amperes.
6. If the current draw exceeds 3.5 amperes check the output arm for binding or damage before replacing motor.