Buick Regal: DTC B0081 (Passenger Presence Module)

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 00

Passenger Presence Module Malfunction (sets in the Inflatable Restraint Sensing and Diagnostic Module)

DTC B0081 11

Passenger Presence Module Above Threshold (Build Check Failure) (sets in the Passenger Presence Module)

DTC B0081 3A

Passenger Presence Module Incorrect Component Installed (sets in the Inflatable Restraint Sensing and Diagnostic Module)

DTC B0081 4B

Passenger Presence Module Calibration Not Learned (sets in the Passenger Presence Module)

DTC B0081 5A

Passenger Presence Module Plausibility Failure (sets in the Passenger Presence Module)

DTC B0081 71

Passenger Presence Module Invalid Serial Data Received (sets in Inflatable Restraint Sensing and Diagnostic Module)

Circuit/System Description

When the ignition is turned ON, the Passenger Presence Module and the Inflatable Restraint Sensing and Diagnostic Module performs tests to diagnose critical malfunctions within itself. When the Inflatable Restraint Sensing and Diagnostic Module has completed the power-up mode, the Inflatable Restraint Sensing and Diagnostic Module will establish communication with the Passenger Presence Module. The Inflatable Restraint Sensing and Diagnostic Module will also request the instrument panel cluster to illuminate both of the PASSENGER AIR BAG ON/OFF indicators for 5 seconds. If the Inflatable Restraint Sensing and Diagnostic Module detects that the Passenger Presence Module has set a current DTC, the Inflatable Restraint Sensing and Diagnostic Module will then disable the passenger instrument panel air bag deployment loop, set DTC B0081, and illuminate the AIR BAG indicator.

Conditions for Running the DTC

Ignition voltage is between 9 - 16 V.

Conditions for Setting the DTC

Any of the following conditions must exist for 5 seconds:

B0081 00

The Inflatable Restraint Sensing and Diagnostic Module has a general fault present.

B0081 11

The Passenger Presence Module is above maximum threshold. The Passenger Presence Module failed the preload/build check.

B0081 3A

The Inflatable Restraint Sensing and Diagnostic Module has received a mismatch message indicating the wrong Passenger Presence Module is installed on the vehicle.

B0081 4B

The Passenger Presence Module is not calibrated. Preload procedure has not been run.

B0081 5A

The Passenger Presence Module detects a plausibility error.

B0081 71

The Inflatable Restraint Sensing and Diagnostic Module has received invalid or no serial data from the Passenger Presence Module.

Action Taken When the DTC Sets

• The inflatable restraint sensing and diagnostic module requests the instrument cluster to illuminate the AIR BAG indicator.
• The passenger instrument panel air bag 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 inflatable restraint sensing and diagnostic module or passenger presence module were replaced verify that the correct part numbers were used for the vehicle application.

Reference Information

Schematic Reference

SIR Wiring Schematics

Connector End View Reference

Component Connector End View Index

Description and Operation

Supplemental Inflatable Restraint System Description and Operation

Electrical Information Reference

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

Scan Tool Reference

K85 Passenger Presence Module: Scan Tool Information for scan tool information.

Circuit/System Verification

NOTE:

• When removing connectors inspect for damage, corrosion or poor connection. Damage or corrosion in the following requires repair or replacement of the affected component/connector.
• Passenger Presence Module
• Inflatable Restraint Sensing and Diagnostic Module
• Passenger Presence Module harness connector
• Inflatable Restraint Sensing and Diagnostic Module wiring harness connector

1. Ignition ON, verify that DTC B0081 is the only DTC set in the Inflatable Restraint Sensing and Diagnostic Module or Passenger Presence Module.

• If any other DTCs are set, refer to Diagnostic Trouble Code (DTC) List - Vehicle.

2. Verify DTC B0081 00, DTC B0081 3A, or DTC B0081 71 is not set in the Inflatable Restraint Sensing and Diagnostic Module. If any of these DTCs set in the Inflatable Restraint Sensing and Diagnostic Module diagnose the following:

• Inflatable Restraint Sensing and Diagnostic Module DTC B0081 00:
  • If DTC B0081 00 sets in the Inflatable Restraint Sensing and Diagnostic Module then refer to step 3 and diagnose the Passenger Presence Module DTC B0081 5A. By diagnosing the Passenger Presence Module DTC B0081 5A, DTC B0081 00 will be fixed in the Inflatable Restraint Sensing and Diagnostic Module.
• Inflatable Restraint Sensing and Diagnostic Module DTC B0081 3A:
  • Either an incorrect replacement Passenger Presence Module or Inflatable Restraint Sensing and Diagnostic Module was placed in this vehicle. Check and make sure the part numbers are correct for each module. If the part numbers are correct clear this DTC and see if DTC B0081 3A resets as a current DTC. If DTC B0081 3A resets then replace the Passenger Presence Module. Clear DTCs again and check if DTC B0081 3A sets as current again. If DTC B0081 3A sets again then replace the Inflatable Restraint Sensing and Diagnostic Module.
• Inflatable Restraint Sensing and Diagnostic Module DTC B0081 71:
  • If DTC B0081 71 sets in the Inflatable Restraint Sensing and Diagnostic Module then refer to the applicable Circuit/System Testing.

3. DTC B0081 11, DTC B0081 4B, or DTC B0081 5A is set in the Passenger Presence Module, diagnose the following:

• Passenger Presence Module DTC B0081 11:
  • If DTC B0081 11 sets in the Passenger Presence Module if the correct calibration was not learned by the Passenger Presence Module. Make sure there is nothing on the passenger seat, not even a scan tool. Perform the Passenger Presence Module Preload procedure, refer to Passenger Presence System Re-Zeroing. Clear the DTC's and check if DTC B0081 11 sets again in the Passenger Presence Module. If DTC B0081 11 sets again replace the Passenger Presence Module.
• Passenger Presence Module DTC B0081 4B:
  • If DTC B0081 4B sets in the Passenger Presence Module if the correct calibration was not learned by the Passenger Presence Module. Make sure there is nothing on the passenger seat, not even a scan tool. Perform the Passenger Presence Module Preload procedure, refer to Passenger Presence System Re-Zeroing. Clear the DTC's and check if DTC B0081 11 sets again in the Passenger Presence Module. If DTC B0081 11 sets again replace the Passenger Presence Module.
• Passenger Presence Module DTC B0081 5A:
  • If DTC B0081 5A sets in the Passenger Presence Module check the connections at the Inflatable Restraint Sensing and Diagnostic Module and Passenger Presence Module. Clear the DTC's and check if DTC B0081 5A sets again as a current DTC in the Passenger Presence Module. If DTC B0081 5A sets then replace the Passenger Presence Module. Clear DTCs again and check if DTC B0081 5A sets as current again. If DTC B0081 5A sets again then replace the Inflatable Restraint Sensing and Diagnostic Module.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

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