Air Bag Systems: Testing and Inspection

Inspection and Verification

WARNING: TO AVOID ACCIDENTAL DEPLOYMENT AND POSSIBLE PERSONAL INJURY, THE BACKUP POWER SUPPLY MUST BE DEPLETED BEFORE REPAIRING OR REPLACING ANY AIR BAG SUPPLEMENTAL RESTRAINT SYSTEM (SRS) COMPONENTS. TO DEPLETE THE BACKUP POWER SUPPLY ENERGY, DISCONNECT THE BATTERY GROUND CABLE AND WAIT TWO MINUTES. FAILURE TO FOLLOW THIS INSTRUCTION MAY RESULT IN PERSONAL INJURY.

CAUTION: Diagnosis by substitution from a donor vehicle is NOT acceptable. Substitution of control modules does not guarantee confirmation of a fault, and may also cause additional faults in the vehicle being tested and/or the donor vehicle.

NOTE:
Given the legal implications of a restraints system failure, harness repairs to Air Bag module circuits are not acceptable. Where the text refers to "REPAIR the circuit", this will normally mean the replacement of a harness.
1 Verify the customer concern.
2 Visually inspect for obvious signs of damage.





3 If an obvious cause for an observed or reported concern is found, correct the cause (if possible) before proceeding to the next step
4 If the cause is not visually evident, check Restraints Control Module (RCM) and Occupancy Classification System (OCS) module for Diagnostic Trouble Codes (DTCs) and refer to the DTC Index.
Given the complexity of the system and the potential for damage/injury, the preferred method of diagnosis is via the Manufacturer approved diagnostic system.
If the Manufacturer approved diagnostic system is not available, use a scan tool to extract DTCs and refer to the DTC Index.


DTC Index

NOTE:
If the control module is suspect and the vehicle remains under manufacturer warranty, refer to the Warranty Policy and Procedures manual (section B1.2), or determine if any prior approval programme is in operation, prior to the installation of a new module.

NOTE:
Generic scan tools may not read the codes listed, or may read only five digit codes. Match the five digits from the scan tool to the first five digits of the seven digit code listed to identify the fault (the last two digits give additional information read by the manufacturer approved diagnostic system).

NOTE:
When performing electrical voltage or resistance tests, always use a digital multimeter (DMM) accurate to three decimal places, and with an up-to-date calibration certificate. When testing resistance, always take the resistance of the DMM leads into account.

NOTE:
Check and rectify basic faults before beginning diagnostic routines involving pinpoint tests.

NOTE:
Inspect connectors for signs of water ingress, and pins for damage and/or corrosion.

NOTE:
If DTCs are recorded and, after performing the pinpoint tests, a fault is not present, an intermittent concern may be the cause. Always check for loose connections and corroded terminals.
For a complete list of all Diagnostic Trouble Codes (DTCs) that could be logged on this vehicle, please refer to Section 100-00
For additional information, refer to Diagnostic Trouble Code (DTC) Index - DTC: Restraints Control Module (RCM)