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For 1990-2009 cars only
Makes 🢒 Isuzu 🢒 2007 🢒 Ascender - 2WD 🢒 Diagnostic Navigation 🢒 Vehicle Diagnostic Information 🢒 Passenger Presence System Indicator Circuit Malfunction

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

Circuit Description

The PASSENGER AIR BAG ON/OFF indicators located on the rearview mirror are used to notify the driver when the passenger presence system (PPS) has enabled or disabled the instrument panel (I/P) inflator module. The PPS air bag indicators will also inform the driver of any PPS malfunctions. When the ignition is turned on, the PPS module is supplied with ignition 1 voltage and commands both PASSENGER AIR BAG ON/OFF indicators ON for 5 seconds. The PPS module conducts tests on the PPS components and circuits while both PASSENGER AIR BAG ON/OFF indicators are ON. If no malfunctions are detected the PPS module will turn the PASSENGER AIR BAG indicator ON or OFF depending on the status of the PPS. If a malfunction is detected, the PPS module will store a DTC, default the PPS to the OFF state and communicate with the SDM that a DTC has been set. The SDM will request the instrument panel cluster (IPC) to turn the AIR BAG indicator ON to notify the driver of a PPS malfunction.

Diagnostic Aids

Use this procedure to diagnosis one or both PPS indicators inoperative.

The following can cause an intermittent condition:

    • A short in the passenger air bag OFF indicator control circuit
    • A short in the passenger air bag ON indicator control circuit
    • An open or high resistance in the passenger air bag OFF indicator control circuit
    • An open or high resistance in the passenger air bag ON indicator control circuit

Reference Information

Schematic Reference

SIR Schematics

Connector End View Reference

    •  SIR Connector End Views
    •  Mirror Connector End Views

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

Circuit/System Testing
  1. With the ignition OFF, disconnect the inside rearview mirror connector located at the back of the mirror. Inspect the mirror connector for damage or corrosion that may cause a malfunction.
    2. ⇒If a condition exists, make the appropriate repair.
  2. Ignition ON, test the ignition 1 voltage circuit for 9-16 volts. If ignition 1 voltage is not present, test for an open/high resistance or a short to ground.
    3. ⇒If a condition exists, make the appropriate repair.
  3. With the ignition OFF, connect a test lamp between the ignition 1 voltage circuit and the passenger air bag OFF indicator control circuit at the inside rearview mirror connector terminals. Ignition ON, test lamp should illuminate.
    4. ⇒If the test lamp illuminates, replace the inside rearview mirror. Refer to repair instructions.
  4. Test the passenger air bag OFF indicator control circuits for a short to ground, open/high resistance.
    5. ⇒If a condition exists, make the appropriate repair.
  5. Replace the PPS.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  SIR/SRS Wiring Repairs
    •  Control Module References for inside rearview mirror and PPS replacement, setup, and programming