Sensor Leakage Test
Connect an ohmmeter between chassis ground and one of the two contacts of sensor lead plug (See illustration ). Resistance should be infinite. Repeat check with ohmmeter connected to other sensor contact. If resistance is not within limits on both checks, disconnect sensor lead plug from sensor at rear axle pinion housing. Repeat resistance checks at sensor plug connector. If the resistance is within specifications, problem is in wiring harness between sensor and module.