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 Descriptors

DTC B0081 0F: Passenger Presence System Erratic

DTC B0081 11: Passenger Presence System Above Threshold (Build Check Failure)

DTC B0081 3A: Passenger Presence System Incorrect Component Installed

DTC B0081 4B: Passenger Presence System Calibration Not Learned

DTC B0081 5A: Passenger Presence System Plausibility Failure

DTC B0081 71: Passenger Presence System Invalid Serial Data Received

Circuit/System Description

When the ignition is turned ON, the passenger presence system (PPS) and the inflatable restraint sensing and diagnostic module (SDM) performs tests to diagnose critical malfunctions within itself. When the SDM has completed the power-up mode, the SDM will establish communication with the PPS. The SDM will also request the instrument panel cluster to illuminate both of the PASSENGER AIR BAG ON/OFF indicators for 5 seconds. If the SDM detects that the PPS has set a current DTC, the SDM will then disable the instrument panel (I/P) module deployment loop, set DTC B0081, and illuminate the AIR BAG indicator.

Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

Conditions for Setting the DTC

Any of the following conditions must exist for 5 seconds:

B0081 0F

    • The SDM has received a fault present message from the PPS.
    • The PPS is in assembly plant mode and the SDM is in production mode.

B0081 11

The PPS is above maximum threshold. The PPS module failed the preload/build check.

B0081 3A

The SDM has received a mismatch message indicating the wrong PPS is installed on the vehicle.

B0081 4B

The PPS is not calibrated. Preload/build check test not run.

B0081 5A

The PPS detects a plausibility error.

B0081 71

The SDM has received invalid or no serial data from the PPS.

Action Taken When the DTC Sets

    • The SDM requests the instrument panel cluster (IPC) to illuminate the AIR BAG indicator.
    • The I/P module deployment loop will be disabled.

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.

Diagnostic Aids

If either the SDM or PPS were replaced, verify that the correct part numbers were used for the vehicle application.

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

Scan Tool Reference

Control Module References for scan tool information

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:

   • PPS module
   • SDM
   • PPS module harness connector
   • SDM wiring harness connector

  1. Ignition ON, verify no PPS DTCs are set.
  2. If any PPS DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle.
  3. Verify that DTC B0081 3A is not set.
  4. If DTC B0081 3A is set, verify that the correct PPS is installed. If the incorrect PPS is installed, replace with the correct part number.
  5. Verify that DTC B0081 4B is not set.
  6. If DTC B0081 4B is set, refer to Passenger Presence System Preload Test
  7. Verify that DTC B0081 11 is not set.
  8. If DTC B0081 11 sets, perform the preload test. If the preload test fails, repeat the test. Refer to Passenger Presence System Preload Test.
  9. Verify that DTC B1325 is not set.
  10. If DTC B1325 is set, refer to DTC B1325
  11. Ignition OFF, disconnect the harness connector at the PPS module.
  12. Ignition OFF, test for less then 10 ohms between the ground circuit terminal 4 and ground.
  13. If greater then the specified range, test the ground circuit for an open/high resistance.
  14. Ignition ON, verify a test lamp illuminates between the B+ circuit terminal 3 and ground.
  15. If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
  16. Reconnect all PPS components and perform the Passenger Presence System Preload Test.
  17. Clear all DTCs and operate the vehicle. DTC. DTC B0081 should not set.
  18. If DTC B0081 sets, replace the PPS.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

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