Component Tests and General Diagnostics

Mini ISO Relay

Terminals:

Use 73 Digital Multimeter to check for the continuity between terminal 2 and all other terminals. If resistance is 5 ohms or less between terminal 2 and any other terminal, replace the relay. If resistance is greater than 5 ohms, continue with the test. Use two jumper wires to connect relay terminals 1 and 3 directly to the positive battery terminal With 73 Digital Multimeter set in the volts position, check for voltage at terminal 4. If battery voltage is not indicated, replace the relay. If battery voltage is indicated, connect a third jumper wire to terminal 2 and ground the jumper wire to a known good ground. Check for voltage at terminal 5. If battery voltage is not indicated, replace the relay.

Wiper Motor Current Draw Test

CAUTION: Do not handle the windshield wiper motor abusively when diagnosing the wiper operations. Failure to follow this caution may result in damage to the motor magnets and will make the windshield wiper motor inoperative. Rough handling of new replacement windshield wiper motors may also damage the motor magnets.

Use Alternator, Regulator, Battery and Starter Tester (ARBST) to test the wiper motor on the vehicle.

To test the wiper motor, disconnect the wiper mounting arm and pivot shaft from the wiper motor.

Disconnect the wiper motor connector. Connect the (A) green lead from the (B) ARBST to the battery negative (-) post. Connect the (C) red lead from the tester to the wiper motor (D) common brush terminal (terminal 3).

Test the low speed mode by connecting a (E) cable from the battery positive (+) post to the (F) low speed brush terminal (terminal 4) and measure the current draw. If the current draw is greater than 3.5 amperes, replace the wiper motor.

Test the high speed mode by connecting a cable from the battery positive (+) post to the (G) high speed brush terminal (terminal 5) and measure the current draw. If the current draw is greater than 5.5 amperes, replace the wiper motor.