B1125

CIRCUIT DESCRIPTION
When the ignition is turned ON, the Inflatable Restraint Sensing And Diagnostic Module (SDM) performs tests to diagnose critical malfunctions within itself. Then the SDM measures the ignition positive voltage in order to ensure that the voltage is within the respective normal voltage range. During a frontal crash of sufficient force the inflatable restraint sensing and diagnostic module (SDM) will allow current to flow through the deployment loop in order to deploy the inflatable restraint steering wheel module. The SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. If a malfunction is detected, a DTC will be stored in non-volatile memory.

CONDITIONS FOR RUNNING THE DTC
Ignition 1 Voltage is within the normal operating voltage range.

CONDITIONS FOR SETTING THE DTC
Steering wheel module or IP module deployment loops are not less than 4.0 volts for 500 milliseconds.

ACTION TAKEN WHEN THE DTC SETS
The SDM commands the AIR BAG warning indicator ON via Class 2 serial data.

CONDITIONS FOR CLEARING THE DTC
^ The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.
^ A history DTC will clear once 255 malfunction free ignition cycles have occurred.

DIAGNOSTIC AIDS
^ The SDM wiring harness connector.
^ The wire to terminal connection, open, or short in the steering wheel module high and/or low circuit.
^ The wire to terminal connection, open, or short in the IP module high and/or low circuit.

If any of the above conditions are found refer to Diagnostic Aids for Circuit Testing and Wiring Repair procedures.

Noting the value of the driver senselo and the passenger senselo during diagnosis can be helpful in determining if an intermittent condition exists. An intermittent open in the inflatable restraint steering wheel module coil could also set this DTC. In order to test for a bad inflatable restraint steering wheel module coil, monitor the driver senselo while you turn the steering wheel back and forth when you turn ON the ignition switch. If the driver senselo changes while you are turning the steering wheel, a malfunction in the inflatable restraint steering wheel module coil is likely.

TEST DESCRIPTION

Steps 1-5:

Steps 6-10:

Steps 11-15:

The numbers below refer to the step numbers on the diagnostic table:
6. Test to see if the malfunction is caused by the steering wheel module coil and/or steering wheel module.
9. Tests for a short to voltage the steering wheel module high and steering wheel module low circuits.
12. Tests for a short to voltage the IP module high and IP module low circuits.