B1126

Circuit Description
When you first turn the ignition switch to the RUN position, the Inflatable Restraint Sensing and Diagnostic Module (SDM) performs tests in order to diagnose critical malfunctions within the module. The SDM measures ignition positive voltage in order to ensure that the voltage is within the respective normal voltage range. The SDM proceeds with the DEPLOYMENT LOOP CONTINUITY test. During the DEPLOYMENT LOOP CONTINUITY test, the SDM measures the voltage difference between the DRIVER HIGH and the DRIVER LOW.

Conditions for Setting the DTC
^ The voltage difference between the DRIVER HIGH terminal 10 and the DRIVER LOW terminal 9 is more than or equal to 426 millivolts.
^ The malfunction must be present for at least 500 milliseconds during one of the following tests:
- DEPLOYMENT LOOP CONTINUITY.
If the malfunction is detected in this test, the RESISTANCE MEASUREMENT test will not be performed.
- CONTINUOUS MONITORING.

Action Taken When the DTC Sets
^ The SDM sets a diagnostic trouble code.
^ The SDM commands the instrument panel cluster (IPC) in order to turn ON the AIR BAG warning lamp.

Conditions for Clearing the MIL/DTC
The DTC will clear when one of the following conditions is met:
^ Current DTC.
The voltage difference between the DRIVER HIGH terminal 10 and the DRIVER LOW terminal 9 is less than 426 millivolts for 500 milliseconds.
^ History DTC.
- You issue a scan tool CLEAR CODES command.
- 250 malfunction free ignition cycles have occurred.

Diagnostic Aids
The following conditions may cause an intermittent condition:
^ A poor connection at the Inflatable Restraint Steering Wheel Module column connector terminals A and B.
^ A poor connection at the upper Inflatable Restraint steering wheel coil connector terminals A and B.
^ A poor connection at the SDM terminals 10 and 9.
^ An open in circuit 347.
^ An open in circuit 348.

An intermittent open in the Inflatable Restraint Steering Wheel Module Coil may also set this DTC. In order to test for a bad Inflatable Restraint Steering Wheel Module Coil, clear the DTCs, then turn the steering wheel back and forth while the ignition switch in the RUN position. If the AIR BAG warning lamp comes ON and DTC B1126 has set again, a malfunctioning Inflatable Restraint Steering Wheel Module Coil may exist.

The diagnostic table directs the technician in order to note the scan tool value of the DRIVER VDIF. Comparing the value of the DRIVER VDIF may be helpful in determining if an intermittent condition exists.

When measurements are requested in this table, use the J 39200 Digital Multimeter with the correct terminal adapter from the J 35616-A Connector Test Adapter Kit. When an inspection for proper connection is requested, refer to Intermittents and Poor Connections. When a wire connector or terminal repair is requested, use the J 38125-B Terminal Repair Kit. Refer to Wiring Repair. Intermittents and Poor Connections

Test Description
The numbers below refer to the step numbers on the diagnostic table:
2. This test determines the deployment loop voltage difference measured by the Inflatable Restraint Sensing and Diagnostic Module (SDM).
3. This test inspects for the proper contact or corrosion of the yellow 2-way connector.
10. This test isolates the malfunction to one side of the Inflatable Restraint Steering Wheel Module Coil yellow 2-way connector.
11. This test determines whether the malfunction is due to the Inflatable Restraint Steering Wheel Module or the module coil.
14. This test inspects for proper contact or corrosion of the SDM connector.
19. This test determines whether the malfunction is in circuit 347.
21. This test determines whether the malfunction is in circuit 348.