Operation CHARM: Car repair manuals for everyone.

B0022

Diagnostic Chart (Part 1 Of 2):




Diagnostic Chart (Part 2 Of 2):




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 performs the following continuous diagnostic tests on the deployment loops:
^ Deployment loop voltage out of range test
^ Deployment loop resistance measurement test

If the voltage out of range test detects a short to voltage condition, the resistance measurement test for that deployment loop will not be performed.

CONDITIONS FOR RUNNING THE DTC
^ Ignition 1 voltage is within the normal operating voltage range.
^ Driver frontal deployment loop is not open.
^ Driver frontal deployment loop is not shorted to voltage.
^ Driver frontal deployment loop is not shorted to ground.

CONDITIONS FOR SETTING THE DTC
Driver frontal deployment loop resistance is less than 1.3 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 resistance of the driver frontal deployment loop is at least 1.3 ohms or more for 500 milliseconds.
^ You can issue a CLEAR CODES command.
^ A history DTC will clear once 255 malfunction free ignition cycles have occurred.

DIAGNOSTIC AIDS
The following can cause an intermittent condition:
^ A short between the driver frontal high and the driver frontal low circuits.
^ A malfunctioning shorting bar on the inflatable restraint steering wheel module 2-way connector.
^ A malfunctioning shorting bar on the inflatable restraint steering wheel module coil 2-way connector.
^ Refer to Intermittent and Poor Connections in Diagrams.

TEST DESCRIPTION
The number(s) below refer to the step number(s) on the diagnostic table.
2. This step checks the 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 determines if there is a short between driver frontal high and driver frontal low circuits, or if there is a malfunctioning SDM.