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.

DTC Descriptor

DTC 063: PPS Out of Calibration

Circuit/System Description

The passenger presence system (PPS) is used to monitor the weight of an occupant in the front passenger seat. The PPS is calibrated at the seat assembly plant and cannot be recalibrated at a service center and must be replaced. The PPS continuously monitors itself and if the system becomes out of calibration, DTC 063 will be set. When the PPS detects this DTC within the PPS, it will notify the customer of the enable/disable status by illuminating the OFF indicator on the PASSENGER AIR BAG ON/OFF indicators. Then the PPS will communicate to the sensing and diagnostic module (SDM) through serial data communication circuit that a PPS fault is present. The SDM will then set DTC B0081 indicating a problem within the PPS and will suppress the deployment of the instrument panel (I/P) module and then illuminate the AIR BAG warning indicator.

Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

Action Taken When the DTC Sets

    • The PPS will set a DTC, and then communicate with the SDM.
    • The SDM will set DTC B0081.
    • The SDM disables the I/P module deployment loop.
    • The PPS will illuminate the passenger air bag status OFF indicator.
    • The SDM requests the instrument panel cluster (IPC) to illuminate the AIR BAG warning indicator.

Conditions for Clearing the DTC

DTC 063 is an indication that the PPS is out of calibration. You cannot recalibrate the PPS. Replace the PPS after following the instructions in the Circuit/System Testing.

Diagnostic Aids

The presence of current or history DTCs while attempting to rezero the PPS will cause the PPS module to set DTC 063. Verify that all supplemental inflatable restraint (SIR) and PPS DTCs have been cleared before rezeroing 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 Testing

Ignition ON, clear all SIR and PPS DTCs. Refer to Passenger Presence System Flash Code Procedures. Rezero the PPS using the Passenger Presence System Rezeroing procedure. Verify DTC 063 does not reset.

If DTC 063 resets, replace the PPS module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

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