Operation CHARM: Car repair manuals for everyone.

B0081




DTC B0081 (Tahoe/Yukon Hybrid except 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 module)

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

Circuit/System Description

When the ignition is turned ON, the passenger presence module 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 passenger presence 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 passenger presence module is installed and functioning normally, the SDM will illuminate the passenger air bags ON or OFF indicator based on messages from the passenger presence module. 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 passenger presence module.

B0081 3A

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

B0081 4B

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

B0081 5A

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

Action Taken When the DTC Sets

* The SDM disables the passenger instrument cluster air bag.
* The passenger presence module will illuminate the Passenger Airbag On/Off indicator status as OFF.
* When the passenger presence module sets this DTC, the passenger presence 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 were replaced verify that the correct part numbers were used for the vehicle application.
* If this DTC is set as either current or history it may have been caused by an electronic device. If an electronic device (Computers, MP3 Players, Cell Phones, Diagnostic Scan Tool, etc.) was placed on the passenger seat the passenger presence module may command the passenger air bag indicator to turn on and/or command the passenger seat belt indicator to turn on. Make sure there are no objects on the passenger seat and clear the DTCs. If this DTC resets then perform this diagnostic. If the DTC does not reset there is no further work needed on the passenger presence system.
* If this DTC is set as either current or history it may have been caused by an aftermarket seat heater. The aftermarket seat heater may command the passenger air bag indicator to turn on and/or command the passenger seat belt indicator to turn on. Remove the aftermarket seat heater from the passenger seat and clear the DTCs. If this DTC resets then perform this diagnostic. If the DTC does not reset there is no further work needed on the passenger presence system.

Reference Information
Schematic Reference

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

Component Connector End Views Connector Views
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.

* Passenger presence module

* SDM

* Passenger presence module harness connector

* SDM wiring harness connector


1. Ignition ON, verify that DTC B0081 is the only DTC set in the SDM or passenger presence 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 passenger presence module will set DTC B0081 4B or DTC B0081 5A. Refer to step #3 and diagnose the passenger presence module DTC's. By diagnosing these two DTC's in the passenger presence module, DTC B0081 00 will be fixed in the SDM.

* SDM DTC B0081 3A:

Either an incorrect replacement passenger presence 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 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 SDM.

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

* PPS 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. Perform the Passenger Presence System Rezeroing procedure. Refer to Passenger Presence System Rezeroing Passenger Presence System Rezeroing.

* PPS DTC B0081 5A:

If DTC DTC B0081 5A sets in the passenger presence module check the connections at the SDM and passenger presence module. Clear the DTC's and check if DTC B0081 5A sets again in the passenger presence module. If DTC B0081 5A sets again replace the passenger presence 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 passenger presence system and SDM replacement, setup, and programming