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Seat Belt Indicator Malfunction - Passenger




Seat Belt Indicator Malfunction - Passenger

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this 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.

Diagnostic Fault Information






Circuit/System Description

When an individual is sitting in the passenger seat the passenger presence sensor detects the individual. A signal to the SDM indicates a person is in the passenger seat. The SDM will turn the passenger seat belt indicator on. The passenger 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 passenger seat belt via a hard wire to the passenger air bag disable switch. After receiving the message, the passenger air bag disable switch controls the illumination of the passenger seat belt indicator.

Diagnostic Aids

Objects on the passenger seat can cause the passenger seat belt reminder to be commanded on. Depending on the sensing technology used, a conductive object (computers, MP3 players, cell phones, diagnostic scan tool, wires, a hand, etc.) placed on the passenger seat may cause the Passenger Presence Detection Module to command the passenger air bag indicator ON and/or command the passenger seat belt indicator ON. The fasten seat belt chime will also sound.

Reference Information

Schematic Reference

Seat Belt Schematics [1][2]Electrical Diagrams

Connector End View Reference

Component Connector End Views Sunshade - Left Front

Description and Operation

Seat Belt 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 Programming and Relearning for scan tool information

Circuit/System Testing

Passenger Presence Malfunction

1. Ignition ON.

2. Have someone sit in the passenger seat.

3. With a scan tool verify the Automatic Occupant Sensing Current Front Occupancy Status indicates Occupied.

• If the Automatic Occupant Sensing Current Front Occupancy Status does not indicate Occupied

1. Disconnect the harness connector at the K36 inflatable restraint sensing and diagnostic module.

2. Test for infinite resistance between the following circuits terminal and ground:

* Sensor signal circuit terminal

* Sensor low reference circuit terminal

• If less than infinite resistance, repair the short to ground on the circuit

• If infinite resistance

3. Test for less than 2 ohms in each circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.

• If less than 2 ohms, replace the passenger presence sensor.

• If the Automatic Occupant Sensing Current Front Occupancy Status does indicate Occupied

4. Ignition ON.

5. With a scan tool perform the Passenger Seat Belt Reminder Indicator On/Off Control Function and verify the passenger seat belt indicator turns on and off.

• If the passenger seat belt indicator does not turn on and off

• Refer to Seat Belt Indicator Malfunction.

• If the passenger seat belt indicator does turn on and off

6. With the scan tool monitor the Passenger 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.

• If the Passenger Seat Belt Status parameter does not display Buckled and Unbuckled
Refer to Seat Belt Switch Malfunction.

• If the Passenger Seat Belt Status parameter does display Buckled and Unbuckled

7. Replace the passenger presence sensor.

Seat Belt Switch Malfunction

1. Ignition OFF.

2. Disconnect the harness connector at the appropriate B88 passenger seat belt switch.

3. Test for less than 5 ohms between the ground circuit terminal B and ground.

• If 5 ohms or greater

1. Disconnect the harness connector at the K36 inflatable restraint sensing and diagnostic module.

2. Test for less than 2 ohms in each control circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.

• If less than 2 ohms, replace the K36 inflatable restraint sensing and diagnostic module.

• If less than 5 ohms

4. Ignition ON.

5. Verify the scan tool Passenger Seat Belt Status parameter listed below is Buckled.

• If the scan tool Passenger Seat Belt Status parameter does not display Buckled

1. Disconnect the harness connector at the K36 inflatable restraint sensing and diagnostic module.

2. Test for infinite resistance between the seat belt switch signal circuit terminal 2 and ground.

• If less than infinite resistance, repair the short to ground on the circuit.

• If less infinite resistance, replace the K36 inflatable restraint sensing and diagnostic module.

• If the scan tool Passenger Seat Belt Status parameter does display Buckled

6. Install a 3 A fused jumper wire between the signal circuit terminal A and the ground circuit terminal B.

7. Verify the scan tool Passenger Seat Belt Status parameter is Unbuckled.

• If the scan tool Passenger Seat Belt Status parameter does not display Unbuckled

1. Disconnect the harness connector at the K36 inflatable restraint sensing and diagnostic module.

2. Ignition ON.

3. Test for less than 1 V between the signal circuit and ground.

• If 1 V or greater, repair the short to voltage on the circuit.

• If less than 1 V

4. Test for less than 2 ohms in each circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.

• If less than 2 ohms, replace the K36 inflatable restraint sensing and diagnostic module.

• If the scan tool Passenger Seat Belt Status parameter does display Unbuckled

8. Ignition OFF, reconnect all harness connectors. Ignition ON.

9. With a scan tool, monitor the Passenger 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.

• If the Passenger Seat Belt Status parameter does not display Buckled and Unbuckled
Test or replace the B88 passenger seat belt switch.

• If the Passenger Seat Belt Status parameter does display Buckled and Unbuckled

10. All OK.

Seat Belt Indicator Malfunction

1. Ignition OFF.

2. Disconnect the harness connector at the P14 passenger air bag disable indicator.

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

• If 5 ohms or greater

1. Disconnect the harness connector at the K36 inflatable restraint sensing and diagnostic module.

2. Test for less than 2 ohms in each control circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.

• If less than 2 ohms, replace the K36 inflatable restraint sensing and diagnostic module.

• If less than 5 ohms

4. Connect a test lamp between the control circuit terminal 5 and ground.

5. Ignition ON.

6. Command the Passenger Seat Belt Reminder ON and OFF with a scan tool, the test lamp should turn ON and OFF while changing between the commanded states.

• If the test lamp is always on

1. Ignition OFF.

2. Disconnect the harness connector at the K36 inflatable restraint sensing and diagnostic module.

3. Ignition ON.

4. Test for less than 1 V between the signal circuit and ground.

• If 1V or greater, repair the short to voltage on the circuit.

• If less than 1V, replace the K36 inflatable restraint sensing and diagnostic module.

• If the test lamp is always off

1. Disconnect the harness connector at the K36 inflatable restraint sensing and diagnostic module.

2. Test for infinite resistance between the seat belt switch signal circuit terminal 4 and ground.

• If less than infinite resistance, repair the short to ground on the circuit.

3. Test for less than 2 ohms in each control circuit end to end.

• If 2 ohms or greater, repair the open/high resistance in the circuit.

• If less than 2 ohms, replace the K36 inflatable restraint sensing and diagnostic module.

• If test lamp turns on and off while changing between the commanded states

7. Replace the P14 passenger air bag disable indicator.

Component Testing

1. Ignition OFF.

2. Disconnect the harness connector at the appropriate B88 passenger seat belt switch.

3. B88 seat belt buckle in the buckled position.

4. Test for infinite resistance between the signal circuit terminal A and the ground terminal B at the B88 passenger seat belt switch.

• If less than infinite resistance
Replace the B88 passenger seat belt switch.

• If infinite resistance

5. B88 seat belt switch in the unbuckled position.

6. Test for less than 2 ohms between the signal circuit terminal A and the ground terminal B at the B88 passenger seat belt switch.

• If 2 ohms or greater
Replace the B88 passenger seat belt switch.

• If less than 2 ohms

7. All OK.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the repair

* Inflatable Restraint Instrument Panel Module Indicator Replacement Service and Repair

* Front Seat Belt Buckle Replacement Front Seat Belt Buckle Replacement

* Inflatable Restraint Front Passenger Presence Sensor Replacement Service and Repair

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

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