Disconnect the connector (A).

Test the wiper motor by connecting 12 volt battery power to terminal No. 1 and ground to terminal No. 2 of the wiper motor. The wiper motor should run at low speed.

Test the wiper motor by connecting 12 volt battery power to terminal No. 3 and ground to terminal No. 2 of the wiper motor. The wiper motor should run at high speed.

Connect an analog ohmmeter wiper to terminals No. 2 and No. 4, and run the wiper motor at low or high speed. The needle of the ohmmeter should pulse. If the wiper motor does not run or fails to run smoothly, or there is no pulse, replace the wiper motor (B) or the wiper linkage.

Disconnect the connector (A).

Test the wiper motor by connecting 12 volt battery power to terminal No. 1 and ground to terminal No. 2 of the wiper motor. The wiper motor should run.

Connect an analog ohmmeter to terminals No. 2 and No. 3, The ohmmeter should indicate continuity and no continuity alternately. If the wiper motor does not run or fails to run smoothly, or there is no pulse, replace the rear window wiper motor (B).