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 and overview of each diagnostic category.

DTC Descriptor

DTC 1051: PPS Initialization/Preload 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 outboard 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 has been replaced a preload test must be run on the serviced seat before that vehicle is released back to the customer. When a new PPS is installed a DTC will set indicating that a preload test needs to be preformed. If the PPS detects any preload DTC, the PPS will communicate to the SDM through a dedicated serial data circuit that a PPS fault is present. The SDM will set DTC B0081 indicating a problem within the PPS, suppress deployment of the I/P module, and illuminate the AIR BAG indicator.

Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

Conditions for Setting the DTC

The PPS will set this DTC when replaced.

Action Taken When the DTC Sets

    • The PPS will set DTC 1051 and communicate the fault to the SDM.
    • The SDM will set DTC B0081 and request the instrument panel cluster (IPC) to illuminate the AIR BAG indicator.
    • The SDM disables the I/P module deployment loop.
    • The PPS will illuminate the passenger air bag status OFF indicator.

Conditions for Clearing the DTC

    • The condition for setting the DTC no longer exists.
    • A history DTC will clear once 100 malfunction-free ignition cycles have occurred.

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

  1. Verify DTC 1051 is not set.
  2. If DTC 1051 is set, refer to Passenger Presence System Programming and Setup.
  3. Verify that DTC 1052, 1053, 1054, or 1055 is not set.
  4. If any of the DTCs are set, refer to DTC 1052, 1053, 1054, or 1055.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for PPS module replacement, setup, and programming