For 1990-2009 cars

### 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.

### DTC Descriptors

DTC 1058: PPS Communication Fault
DTC 1059: PPS Communication Fault
DTC 1060: PPS Communication Fault
DTC 1061: PPS Communication Fault
DTC 1062: PPS Communication Fault

### Circuit/System Description

The passenger presence system (PPS) is used to monitor the pressure profile of any occupant that is sitting in the front passenger seat and communicates the profile classification to the sensing and diagnostic module (SDM). The SDM will either enable or suppress the deployment of the instrument panel (I/P) module based on the profile classification of the occupant. If the PPS detects that a malfunction with the communication circuit then the PPS will then set a DTC within the PPS. The SDM will then set DTC B0081 indicating a problem within the PPS and will suppress the deployment of the I/P module and then turn the airbag indicator ON.

### Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

### Conditions for Setting the DTC

The PPS has never established or lost communications with the SDM.

### Action Taken When the DTC Sets

• | The PPS will set a DTC, and then communicate with the SDM via non GMLAN circuit.

• | The SDM will set DTC B0081.

• | The SDM disables the I/P module deployment loop.

• | The PPS will turn ON the passenger air bag status OFF indicator.

• | The SDM commands the AIR BAG indicator ON via serial data communications.

### Conditions for Clearing the DTC

• | When conditions for the DTC to set no longer exist, use CLEAR DTC function of the scan tool to clear the DTC.

• | After 255 consecutive warm-up cycles without failure, the DTC will be cleared.

### Reference Information

#### Schematic Reference

SIR Schematics

#### Connector End View Reference

SIR Connector End Views

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

### Circuit/System Testing

Important: When removing connectors, inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the affected component/connector.

• | The PPS module

• | The SDM module

• | The PPS wiring harness connector

• | The SDM wiring harness connector

1. Ignition ON, use the scan tool. Go to PPS menu, then retrieve the DTCs. Verify DTC 1058-1062 is set.
2. Ignition OFF, disconnect the PPS module connector. Refer to Inflatable Restraint Passenger Presence System Replacement - Front for location of connector.
3. Remove and inspect the SDM connector. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement for location of connector.
4. Test the PPS communication circuit between the SDM and the PPS for a short to voltage, an open, or high resistance. Verify no high resistance, an open, or short to voltage exist.

⇒ | If any of the above conditions are found make the appropriate repair.

5. If all circuits test normal then replace the SDM.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Refer to Control Module References for SDM replacement, setup and programming.