DTC B2502 Expect North America Vehicles

Diagnostic Instructions

DTC Descriptors

DTC B2502 : Passenger Air Bag Disabled Indicator Circuit Malfunction

Circuit/System Description

When the ignition switch is turned to ON, the sensing and diagnostic module (SDM) will perform a turn-on test to diagnose critical malfunctions within the SDM itself.

The SDM continuously checks the cut-off switch position and circuit defect by letting voltage flow through the cut-off switch circuit.

Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

Conditions for Setting the DTC

The passenger OFF indicator lamp does not blink properly.

Action Taken When the DTC Sets

The SDM commands the AIR BAG indicator ON.

Conditions for Clearing the DTC

Reference Information

Schematic Reference

SIR Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

Circuit/System Testing

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

•	The steering wheel coil module

•	The SDM module

•	The steering wheel coil module wiring harness connector

•	The SDM wiring harness connector

1. Remove the clock assembly and check the bulb of the passenger airbag off lamp.

⇒	If bulb is bad, replace the bulb.

2. Ignition OFF, disconnect the clock wiring connector.
3. .
4. Ignition ON, test for 4.75-5.25 V between terminal 6 of the clock wiring connector and ground.

⇒	If voltage is not as specified, repair the open, high resistance or short in the circuit.

5. Disconnect the connector of the passenger airbag disable switch.
6. Test for less than 1 ohm between terminal 10 of the clock and terminal 1 of the disable switch.

⇒	If resistance is not as specified, repair the open or high resistance in the circuit.

⇒	If all circuits test normal, replace the SDM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

DTC B2502 North America Vehicles

Diagnostic Instructions

DTC Descriptors

DTC B2502 : Passenger Air Bag Disabled Indicator Circuit Malfunction

Circuit/System Description

When the ignition switch is turned to ON, the sensing and diagnostic module (SDM) will perform a turn-on test to diagnose critical malfunctions within the SDM itself.

Upon passing these tests, the ignition and deployment loop voltages are measured to ensure that these voltages are within the normal ranges. The SDM monitors the voltages at the driver low and the passenger low to detect shorts to ground or voltage in the deployment loops.

The SDM tests the voltage continuously from the warning lamp terminal.

Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

Conditions for Setting the DTC

The passenger OFF indicator lamp does not operate depending on the status of passenger presence.

Action Taken When the DTC Sets

The SDM commands the AIR BAG indicator ON.

Conditions for Clearing the DTC

Reference Information

Schematic Reference

SIR Schematics

Connector End View Reference

Component Connector End Views

Electrical Information Reference

Circuit/System Testing

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

•	The steering wheel coil module

•	The SDM module

•	The steering wheel coil module wiring harness connector

•	The SDM wiring harness connector

1. Ignition OFF, disconnect the clock assembly connector
2. Inspect the bulb of the passenger air bag ON indicator.

⇒	If bulb is bad, replace the bulb.

3. Ignition ON, test for B+ at terminal 1 of the clock wiring connector

⇒	If voltage is not as specified, repair the open, high resistance or short to ground in the circuit.

4. Ignition OFF, disconnect the sensing and diagnostic module (SDM) connector.
5. Test for less than 1 ohm between terminal 56 of the SDM and terminal 10 of the clock connector.

⇒	If resistance is not as specified, repair the open or high resistance in the circuit.

⇒	If all circuits test normal, replace the SDM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.