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Seat Belt Indicator Circuit Malfunction - Driver

Seat Belt Indicator Circuit Malfunction - Driver

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.


Diagnostic Fault Information

Circuit Short to Ground High Resistance Open Short to Voltage Signal Performance
Driver Seat Belt Switch Signal

1

2

2

2

-

Driver Seat Belt Switch Low Reference

-

2

2

2

-

1. Indicator will remain ON with seat belt buckled.

2. Indicator will illuminate only for the bulb check.



Circuit/System Description

The driver seat belt switch is a 2-wire switch wired to the inflatable restraint sensing and diagnostic module (SDM) using a signal circuit and a low reference circuit. When the seat belt is unbuckled the switch is closed, and when the seat belt is buckled the switch is open. The SDM sends the status of the driver seat belt via serial data to the instrument panel cluster. After receiving the message, the instrument panel cluster controls the illumination of the driver seat belt indicator.

Reference Information

Schematic Reference

Seat Belt Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Seat Belt System Description and Operation

Electrical Information Reference


Circuit Testing

Connector Repairs

Testing for Intermittent Conditions and Poor Connections

Wiring Repairs


Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification


1. Ignition ON, with a scan tool turn on all indicators using the Instrument Cluster Output Controls and verify the driver seat belt indicator is illuminated for 5 seconds.

2. If the indicator does not illuminate, replace the P16 instrument panel cluster.

3. With the scan tool monitor the Driver Seat Belt Status parameter while buckling and unbuckling the seat belt. The parameter should display Buckled and Unbuckled when buckling and unbuckling the seat belt.


Circuit/System Testing


1.
Note

When removing connectors inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the affected component/connector.

B88 Seat belt switch

Seat belt switch harness connector

K36 SDM

SDM wiring harness connector


Ignition OFF, disconnect the harness connector at the B88 seat belt switch.

2. Test for less than 5 Ω between the ground circuit terminal 2 and ground.

3. If greater than the specified range, test the ground circuit for an open/high resistance. If the circuit tests normal replace the K36 SDM.

4. Ignition ON, verify the scan tool Driver Seat Belt Status parameter displays Buckled.

5. If not the specified value, test the signal circuit terminal 1 for a short to ground. If the circuit tests normal replace the K36 SDM.

6. Install a 3 A fused jumper wire between the circuit terminal 1 and the ground circuit terminal 2. Verify the scan tool Driver Seat Belt Status parameter displays Unbuckled.

7. If not the specified value, test the signal circuit for a short to voltage or an open/high resistance. If the circuit tests normal replace the K36 SDM.

8. If all circuits test normal, test or replace the B88 seat belt switch. Refer to Driver or Passenger Seat Belt Buckle Replacement .


Component Testing


1. Ignition OFF, disconnect the harness connector at the B88 seat belt switch.

2. Test for infinite resistance between the signal circuit terminal 1 and the ground terminal 2, at the switch, with the switch in the open position.

3. If not the specified value, replace the B88 seat belt switch. Refer to Driver or Passenger Seat Belt Buckle Replacement .

4. Test for less than 5 Ω between the signal circuit terminal 1 and the ground terminal 2, at the switch, with the switch in the closed position.

5. If greater than the specified range, replace the B88 seat belt switch. Refer to Driver or Passenger Seat Belt Buckle Replacement .


Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for SDM and instrument panel cluster replacement, setup and programming