See Figure 1
- Disconnect the system relay.
- Connect the positive lead of a voltmeter to terminal 3 of the relay connector and the other lead to ground.
- Verify that there is approximately 12 volts with the ignition switch ON . If not as specified, inspect the ABS system fuse and wiring to the relay.
- Turn the ignition switch OFF . Disconnect the system relay and remove from the ABS control unit bracket.
- Connect a jumper wire from the positive battery terminal to terminal 2 of the relay. Connect terminal 4 of the relay to ground. Using and ohmmeter, measure the resistance present at terminals 1 and 3 , while power is supplied. The meter should read continuity.
- Disconnect the power supply and ground from the relay.
- Connect an ohmmeter between terminals 2 and 4 on the relay and check the resistance. Continuity should be present.
- Connect the ohmmeter leads between terminals 1 and 3 and check the resistance. No continuity should be present.
- If the readings are not as specified, replace the relay.
- If the relay test good, inspect the control unit and wiring.