Vehicle Speed Sensor Test (Impulse & Trooper)

1. With instrument cluster removed, use ohmmeter and check continuity across Vehicle Speed Sensor (VSS) terminals. See Fig 1 and Fig 2 .
2. Rotate speedometer shaft slowly and note if reading alternates from continuity to an open circuit 4 times per revolution. Replace speedometer assembly if VSS is defective.

Fig 1: Testing Impulse Vehicle Speed Sensor (VSS)

Courtesy of ISUZU MOTOR CO.

Fig 2: Testing Trooper Vehicle Speed Sensor (VSS)

Courtesy of ISUZU MOTOR CO.

NOTE: If a problem develops with vehicle speed sensor, ECM will set a Code 24. For additional testing procedures, see appropriate TESTS W/CODES article in this section.