B1126

Diagnostic Chart (Part 1 Of 3):

Diagnostic Chart (Part 2 Of 3):

Diagnostic Chart (Part 3 Of 3):

Wiring Diagram:

CIRCUIT DESCRIPTION
When you first turn ON the ignition, 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. The SDM proceeds with the deployment loop continuity test. During the deployment loop continuity test, the SDM measures the voltage difference between the high and low deployment circuits.

CONDITIONS FOR RUNNING THE DTC
Deployment loop voltage out of range test:
^ Ignition 1 voltage is within the normal operating voltage range.
^ Driver frontal deployment loop is not shorted to voltage.
^ The voltage difference between the driver frontal high and low is greater than or equal to 426 millivolts for 500 milliseconds.

DEPLOYMENT LOOP RESISTANCE MEASUREMENT TEST:
^ Ignition 1 voltage is within the normal operating voltage range.
^ Driver frontal deployment loop is not shorted to voltage.
^ Driver frontal deployment loop is not shorted to ground.

CONDITIONS FOR SETTING THE DTC
Deployment loop voltage out of range test - Driver frontal deployment loop is greater than or equal to 426 millivolts for 500 milliseconds.

Deployment loop resistance measurement test - Driver frontal deployment loop resistance is greater than or equal to 250 ohms for 500 milliseconds.

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

CONDITIONS FOR CLEARING THE DTC
^ The voltage difference between the driver frontal high and low circuits are less than 426 millivolts for 500 milliseconds.
^ The driver frontal deployment loop resistance is less than 250 ohms for 500 milliseconds.
^ You can issue a CLEAR CODES command
^ A history DTC will clear once 250 malfunction free ignition cycles have occurred

DIAGNOSTIC AIDS
The following can cause an intermittent condition:
^ The SDM wiring harness connector.
^ The wire to terminal connection or open in the driver frontal high circuit.
^ The wire to terminal connection or open in the driver frontal low circuit.
^ The inflatable restraint steering wheel module harness connector.
^ The inflatable restraint steering wheel module coil harness connector.

If any of the above conditions are found refer to Testing for Intermittent and Poor Connections in Diagram. Comparing the value of the DRIVER VDIF may be helpful in determining if an intermittent condition exists.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table:
2. This step checks the driver inflator module in-line connector below the steering wheel restraint module coil.
6. This step test for the proper operation of inflatable restraint steering wheel module coil and/or inflatable restraint steering wheel inflator module.
9. This step checks to see if the inflatable restraint sensing and diagnostic module (SDM) wiring harness connector is OK.
11. This step checks to see if there is an open or a high resistance in the driver frontal high circuit.
13. This step determines if there is an open or a high resistance in the driver frontal low circuit, or if there is a malfunctioning SDM.