Chevrolet Trax: Passenger presence system rezeroing

Introduction

The inflatable restraints passenger presence system is a calibrated system that requires re-zeroing or a zero check anytime the seat cushion trim attachments have been removed or the passenger presence system has been replaced. The procedures below are designed to assist in the re-zeroing of the passenger presence system.

Before you start, read these procedures carefully and completely. For further information regarding the passenger presence system refer to Supplemental Inflatable Restraint System Description and Operation.

NOTE: The following procedures must be followed:

1. Read this procedure carefully and completely.
2. The passenger presence system will not function properly if the passenger presence system re-zeroing procedure is not performed.
3. Perform the Diagnostic Repair Verification after successfully completing the re-zeroing procedure to ensure the system is functioning properly.

Passenger Presence System Re-zeroing Procedure

NOTE:

• Before the passenger presence system can be re-zeroed the front passenger seat must be completely empty of all items. The presence of any liquid or items on the front passenger seat will affect the calibration and operation of the passenger presence system.
• DTC B0081 will set if the re-zero system test is performed with:

• An aftermarket seat heater located too close to the sensor mat
• A scan tool, laptop, or other electronic device is in the seat
• The seat is damp or wet
• An object or person is in the seat

1. Verify that the temperature is between 32ºF to 100ºF before running a re-zero procedure.
2. Verify the seat is completely dry.
3. Empty the front outboard passenger seat.
4. Verify that all SIR and passenger presence system components, connectors, and connector position assurances are properly connected and mounted.
5. Install a scan tool.
6. Turn ON the ignition, with the engine OFF.

NOTE:

The presence of current DTCs, except DTC B0081 11 or B0081 4B, will prevent the passenger presence system from re-zeroing and may set additional DTCs.

7. With a scan tool, perform the Passenger Presence Sensor Learn procedure.
8. If the test fails, confirm that the seat is empty and completely dry. Perform the Passenger Presence Sensor Learn test again. If the test fails again, verify DTC B0081 is not set as current, if the DTC is set refer to Diagnostic Trouble Code (DTC) List - Vehicle . If the test successfully completed, cycle the ignition OFF.
9. After the passenger presence system has been successfully re-zeroed, perform the Diagnostic Repair Verification .

SYMPTOMS - SIR

NOTE:

Complete the following steps before using the symptom tables:

1. Perform Diagnostic System Check - Vehicle before using the symptom tables in order to verify that all of the following are true:

• There are no DTCs set.
• The inflatable restraint sensing and diagnostic module (SDM) can communicate via the serial data link.

2. Review the SIR system description and operation in order to familiarize yourself with the system functions. Refer to Supplemental Inflatable Restraint System Description and Operation.

Visual/Physical Inspection

• Inspect for aftermarket devices which could affect the operation of the SIR system. Refer to Checking Aftermarket Accessories .
• Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.

Intermittent

Faulty electrical connections or wiring may be the cause of intermittent conditions. Refer to Testing for Intermittent Conditions and Poor Connections .

Symptom List

Refer to Airbag Indicator Malfunction in order to diagnose the symptom.

READ NEXT: