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B0081




DTC B0081 (Except Tahoe/Yukon Hybrid/Denali)

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using the diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.

DTC Descriptors
DTC B0081 00
- Passenger Presence Module Erratic (sets in the SDM)

DTC B0081 3A
- Passenger Presence Module Incorrect Component Installed (sets in the SDM)

DTC B0081 4B
- Passenger Presence Module Calibration Not Learned (sets in the passenger presence (PPS) module)

DTC B0081 5A
- Passenger Presence Module Plausibility Failure (sets in PPS module)

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. When the SDM has completed the power-up mode, the SDM will establish communication with the PPS module. The SDM will also request the instrument panel cluster (IPC) to illuminate both of the PASSENGER AIR BAG ON/OFF indicators ON for 5 seconds. If the SDM determines the correct PPS is installed and functioning normally, the SDM will illuminate the passenger air bags ON or OFF indicator based on messages from the PPS. The SDM sends a message to the IPC to illuminate the appropriate PASSENGER AIR BAG ON/OFF indicator.

Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

Conditions for Setting the DTC

All of the following conditions must exist for 5 seconds:

B0081 00

The SDM sets this DTC if there is a fault present in the PPS module.

B0081 3A

The SDM sets this DTC when the SDM has received a message from the PPS module which indicates a mismatch between the SDM and PPS module. There is either an incorrect SDM or PPS module installed on this vehicle.

B0081 4B

The PPS module sets this DTC when the PPS module has not learned the calibrations.

B0081 5A

The PPS module sets this code when the PPS module has lost communications with the SDM.

Action Taken When the DTC Sets

* The SDM disables the passenger instrument cluster air bag.
* The PPS module will illuminate the Passenger Airbag On/Off indicator status as OFF.
* When the PPS module sets this DTC, the PPS module communicates with the SDM to turn the AIRBAG indicator on.
* When the SDM sets this DTC, the SDM will turn the AIRBAG indicator on.
* The SDM requests the instrument panel cluster (IPC) to illuminate the AIRBAG indicator.

Conditions for Clearing the DTC

* The condition for setting the DTC no longer exists and there is no activity on the low speed serial data circuits.
* A history DTC will clear once 100 malfunction-free ignition cycles have occurred.

Diagnostic Aids

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

Reference Information
Schematic Reference

SIR Schematics ([1][2]Air Bag Systems)
Connector End View Reference

Component Connector End Views (Connector End Views By Name)
Description and Operation

SIR System Description and Operation (Description and Operation)
Electrical Information Reference

* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)

Scan Tool Reference

Control Module References (Control Module References) for scan tool information

Circuit/System Verification

Important:
* 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.

* PPS module

* SDM module

* PPS module harness connector

* SDM wiring harness connector


1. Ignition ON, verify that DTC B0081 is the only DTC set in the SDM or PPS module.

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

2. Verify DTC B0081 00, or DTC B0081 3A is not set in the SDM. If any of these DTCs set in the SDM diagnose the following:

* SDM DTC B0081 00:

If DTC B0081 00 sets in the SDM then the PPS module will set DTC B0081 4B or DTC B0081 5A. Refer to step #3 and diagnose the PPS module DTC's. By diagnosing these two DTC's in the PPS module, DTC B0081 00 will be fixed in the SDM.

* SDM DTC B0081 3A:

Either an incorrect replacement PPS module or SDM was placed in this vehicle. Check and make sure the part #'s are correct for each module. If both part #'s are correct clear this DTC and see if DTC B0081 3A resets as a current DTC. If DTC B0081 3A resets then replace the PPS module. Clear DTCs again and check if DTC B0081 3A sets as current again. If DTC B0081 3A sets again then replace the SDM.

3. Verify DTC B0081 4B, or DTC B0081 5A is not set in the PPS module. If either of these DTCs set in the PPS module diagnose the following:

* PPS DTC B0081 4B:

If DTC B0081 4B sets in the PPS module if the correct calibration was not learned by the PPS module. Replace the PPS module.

* PPS DTC B0081 5A:

If DTC DTC B0081 5A sets in the PPS module check the connections at the SDM and PPS module. Clear the DTC's and check if DTC B0081 5A sets again in the PPS module. If DTC B0081 5A sets again replace the PPS module.


Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* SIR/SRS Wiring Repairs (SIR/SRS Wiring Repairs)
* Control Module References (Control Module References) for PPS module and SDM replacement, setup, and programming