Spark

Seat Belt Indicator Circuit Malfunction - Rear

The rear seat belt switches each supply a ground to the SDM when their seat belts are buckled. When a seat belt is unbuckled, a switch opens removing the ground to the SDM. The SDM will then supply voltage to the seat belt indicator which will then cause that indicator to illuminate.

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

Scan Tool Reference

Control Module References for scan tool information

1. Observe the scan tool parameters listed below while buckling and unbuckling the left rear, right rear and middle rear seat belts. The values for each should change from Unbuckled to Buckled.

•	2nd Row Left Seat Belt Status

•	2nd Row Middle Seat Belt Status

•	2nd Row Right Seat Belt Status

⇒	If the values do not change, refer to Seat Belt Switch Malfunction.

2. Command the Driver Seat Belt Reminder ON and OFF with a scan tool, the seat belt indicator should turn ON and OFF while changing between the commanded states.

⇒	If the indicator is always ON or always OFF, refer to Seat Belt Indicator Malfunction.

Seat Belt Switch Malfunction

1. Ignition OFF, disconnect the harness connector at the appropriate B88 seat belt switch.
2. Test for less than 1 Ω between the ground circuit terminal 1 and ground.

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

3. Ignition ON, verify the scan tool Seat Belt Status parameter is Buckled.

⇒	If not the specified value, test the signal circuit terminal 2 for a short to ground. If the circuit tests normal, replace the K36 SDM.

4. Install a 3 A fused jumper wire between the signal circuit terminal 2 and the ground circuit terminal 1. Verify the scan tool Seat Belt Status parameter is Buckled.

⇒	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

5. If all circuits test normal, test or replace the appropriate rear B88 seat belt switch.

Seat Belt Indicator Malfunction

1. Ignition OFF, disconnect the harness connector at the A5 driver information centre.
2. Test for less than 1 Ω between the ground circuit terminal 7 and ground.

⇒	If greater than the specified range, test the ground circuit for an open/high resistance.

3. Connect a test lamp between the control circuit terminal 11 and ground.
4. Ignition ON, command the Driver 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, test the control circuit for a short to voltage. If the circuit tests normal, replace the K36 SDM.

⇒	If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K36 SDM.

5. If all circuit test normal, test or replace the A5 driver information centre.

1. Ignition OFF, disconnect the harness connector at the appropriate rear B88 seat belt switch.
2. Test for infinite resistance between the signal terminal 2 and the ground terminal 1 with the switch in the open position.

⇒	If not the specified value, replace the appropriate rear B88 seat belt switch.

3. Test for less than 2 Ω between the signal terminal 2 and the ground terminal 1 with the switch in the closed position.

⇒	If greater than the specified range, replace the appropriate rear B88 seat belt switch.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.