GM Service Manual Online
For 1990-2009 cars only

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.

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Inside Rear View Mirror Ignition

2, 4

2, 4

--

--

Passenger Air Bag On Indicator Control

1

2

2

--

Passenger Air Bag Off Indicator Control

3

4

4

--

1. Passenger Air Bag On Indicator Always ON

2. Passenger Air Bag On Indicator Always OFF

3. Passenger Air Bag Off Indicator Always ON

4. Passenger Air Bag Off Indicator Always OFF

Circuit/System 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 illuminates both passenger air bag ON/OFF indicators for 5 seconds. The PPS module conducts tests on the PPS components and circuits while both passenger air bag ON/OFF indicators are illuminated. If no malfunctions are detected the PPS module will illuminate the passenger air bag indicator ON or OFF depending on the status of the PPS.

Reference Information

Schematic Reference

SIR Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

SIR System Description and Operation

Electrical Information Reference

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

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

With the passenger seat occupied and unoccupied the inflatable restraint passenger air bag ON/OFF indicator should switch states within 5 seconds.

Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector at the inside rear view mirror.
  2. Ignition ON, verify that a test lamp illuminates between the ignition circuit terminal 4 and ground.
  3. If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance, if the circuit tests normal and the ignition fuse is open, replace the inside rear view mirror.
  4. With the right front passenger seat occupied, verify that a test lamp illuminates between the control circuit terminal 1 and B+.
  5. If the test lamp does not illuminate, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the PPS module.
  6. With the right front passenger seat vacant, verify that a test lamp does not illuminate between the control circuit terminal 1 and B+.
  7. If the test lamp illuminates, test the control circuit for a short to ground. If the circuit tests normal, replace the PPS module.
  8. With the right front passenger seat vacant, verify that a test lamp illuminates between the control circuit terminal 3 and B+.
  9. If the test lamp does not illuminate, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the PPS module.
  10. With the right front passenger seat occupied, verify that a test lamp does not illuminate between the control circuit terminal 3 and B+.
  11. If the test lamp illuminates, test the control circuit for a short to ground. If the circuit tests normal, replace the PPS module.
  12. If all circuits test normal, test or replace the inside rear view mirror.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Inside Rearview Mirror Replacement
    •  Control Module References for PPS module replacement, setup, and programming