Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS)
Air Bag and Safety Belt Pretensioner Supplemental Restraint System (SRS)
Special Tools
General Equipment
Diagnosing Customer Concerns Without Hard Diagnostic Trouble Codes (DTCs)
If a lamp fault code (LFC) is reported by the customer but is not present when the vehicle comes in for service, follow the Diagnostic Instructions procedure in this section to identify the intermittent DTC.
Once the DTC is known, read the Normal Operation section of the pinpoint test for the DTC involved.
Follow the deactivation procedure in this section.
Determine the location of components involved in creating the DTC.
Carry out a thorough visual inspection of:
components
connectors
splices and wiring harnesses
insulation on conductors
Refer to Possible Causes section of the pinpoint test for the DTC involved, which lists the common concerns that relate to the DTC. Concerns are listed according to priority.
Diagnosing Customer Concerns With Hard Diagnostic Trouble Codes (DTCs)
Most supplemental restraint system (SRS) diagnostic procedures will require the use of the deactivation and reactivation or depowering and repowering of the system. Deactivation and reactivation requires the disconnection of most SRS components and the installation of restraint system diagnostic tools. Depowering and repowering requires disconnecting of the battery and removal of the restraints control module (RCM) fuse. This reduces the risk of inadvertent deployment of SRS components while diagnostic procedures are being carried out.
Restraint system diagnostic tools are required for the diagnosis and testing of the SRS. It is not acceptable to short-circuit the air bag module connections with a jumper wire because a lamp fault code (LFC) will be displayed.
Prove Out Procedure
Turn the ignition switch from the OFF to the ON position and visually monitor the air bag indicator with all SRS components connected or restraint system diagnostic tools installed. The air bag indicator will light continuously for approximately six seconds and then turn off. If an SRS fault is present, the air bag indicator will either:
fail to light.
remain lit continuously.
flash.
The flashing might not occur until approximately 30 seconds after the ignition switch has been turned from the OFF to the ON position. This is the time required for the restraints control module (RCM) to complete the testing of the SRS. If the air bag indicator is inoperative and an SRS fault exists, a chime will sound in a pattern of five sets of five bleeps. If this occurs, the air bag indicator will need to be repaired before diagnosis can continue.
Glossary
Secondary Air Bag Warning
The secondary air bag warning is an audible fault format that consists of five sets of five tone bursts, with each set of five tone bursts separated by a five second quiet period. One tone burst cycle will consist of one second ON and one second OFF. This series of five activations is repeated every 30 minutes.
Air Bag/Pretensioner Restraint System Diagnostic Tools
Air bag/pretensioner restraint system diagnostic tools are used to simulate the equivalent resistance of an air bag module or safety belt pretensioner during certain diagnostic procedures.
Disconnect the Component
Disconnect the component means to disconnect the component vehicle harness connector, not to remove the component. Do not reconnect a disconnected component unless instructed to do so.
Deactivate the System
Deactivate the system means to carry out a deactivation procedure. For additional information, Service and Repair
Depower the System
Depower the system means to disconnect the battery and remove the restraints control module (RCM) fuse. For additional information, Service and Repair
Prove Out the System
Prove out the system means to turn the ignition switch from the OFF to the ON position, and to visually monitor the air bag indicator with the air bag modules and safety belt pretensioners or restraint system diagnostic tools installed. For additional information, refer to Prove Out Procedure in this section.
Reactivate the System
Reactivate the system means to carry out the reactivation procedure. For additional information, Service and Repair
Air Bag System Reconnect Checklist
All restraint system diagnostic tools removed?
All in-seat harness connectors connected?
All air bag modules connected?
Safety belt pretensioner connectors connected?
Restraints control module (RCM) connected?
All sensors (front and side impact sensors) connected?
Battery connected?
Deactivation Procedure
WARNING: Always wear safety glasses when repairing an air bag supplemental restraint system (SRS) vehicle and when handling an air bag module. This will reduce the risk of injury in the event of an accidental deployment. Failure to follow this instruction may result in personal injury.
WARNING: Never probe the connectors on the air bag module. Failure to follow this instruction may result in accidental air bag deployment, and may result in personal injury.
WARNING: To reduce the risk of personal injury, do not use any memory saver devices. Failure to follow this instruction may result in personal injury.
NOTE: If a seat equipped with a seat mounted side air bag and/or a safety belt pretensioner (if equipped) system is being serviced, the supplemental restraint (SRS) must be depowered.
NOTE: The air bag warning lamp illuminates when the RCM fuse is removed and the ignition switch is ON. This is normal operation and does not indicate a supplemental restraint system (SRS) fault.
NOTE: The SRS must be fully operational and free of faults before releasing the vehicle to the customer.
1. Turn all vehicle accessories OFF.
2. Turn the ignition switch to OFF.
3. At the central junction box (CJB), located below the LH side of the instrument panel, remove the cover and the restraints control module (RCM) fuse F60 (7.5A) from the CJB. For additional information, refer to Wiring Diagram Manual.
4. Turn the ignition ON and visually monitor the air bag indicator for at least 30 seconds. The air bag indicator will remain lit continuously (no flashing) if the correct RCM fuse has been removed. If the air bag indicator does not remain lit continuously, remove the correct RCM fuse before proceeding.
5. Turn the ignition OFF.
6. WARNING: To avoid accidental deployment and possible personal injury, the backup power supply must be depleted before diagnosing, repairing or installing any front or side air bag SRS components and before servicing, installing, adjusting or striking components near the front or side air bag sensors, such as doors, instrument panel, console, door latches, strikers, seats and hood latches. The side air bag sensors (if equipped) are located at or near the base of the B-pillars. To deplete the backup power supply energy, disconnect the battery ground cable and wait at least one minute. Be sure to disconnect auxiliary batteries and power supplies (if equipped). Failure to follow these instructions may result in accidental air bag deployment, and may result in personal injury.
Disconnect the battery ground cable and wait at least one minute.
7. WARNING: Carry a live air bag module with the air bag and trim cover pointed away from your body. This will reduce the risk of injury in the event of an accidental deployment. Failure to follow this instruction may result in personal injury.
WARNING: Do not set a live air bag module down with the trim cover face down. This will reduce the risk of injury in the event of an accidental deployment. Failure to follow this instruction may result in personal injury.
Remove the driver air bag module from the vehicle. Service and Repair
8. Install a driver air bag simulator to the harness side of the driver air bag connector.
9. Remove the instrument panel. Service and Repair
10. Disconnect the passenger air bag electrical connector.
11. Install a passenger air bag simulator to the harness side of the passenger air bag connector.
12. Disconnect the driver side air bag connector beneath the driver seat.
13. NOTE: For vehicles built on or after 05-Feb-00 or if the vehicle is equipped with connector C991 two simulators are required.
Install a side air bag simulator to the harness side of the driver side air bag and connector.
14. NOTE: Passenger side air bag pretensioner uses only one connector.
Repeat Steps 12 and 13 for the passenger side air bag connector.
15. Install the RCM fuse F60 (7.5A) to the CJB.
16. Reconnect the battery ground cable.
Reactivation Procedure
1. WARNING: The air bag and pretensioner simulators must be removed and the air bag modules and safety belt pretensioners must be reconnected when the system is reactivated to avoid non-deployment in a collision. Failure to follow these instructions may result in personal injury.
Disconnect the battery ground cable.
2. Wait at least one minute for the backup power supply in the restraint control module (RCM) to deplete its stored energy.
3. Remove the RCM fuse F60 (7.5A) from the CJB.
4. Remove the driver/passenger air bag simulator from the air bag sliding contact connector.
5. Reinstall the driver air bag module.
6. Remove the driver/passenger air bag simulator from the passenger air bag connector.
7. Reconnect the passenger air bag electrical connector.
8. Install the instrument panel. Service and Repair
9. Remove the driver side air bag/pretensioner simulator (if built on or after 05-Feb-00, also remove the driver pretensioner simulator, Special Tool number 501-301 from C991).
10. Reconnect the driver side air bag/pretensioner connector (if built on or after 05-Feb-00, also reconnect the driver pretensioner C991).
11. Remove the passenger side air bag/pretensioner simulator.
12. Reconnect the passenger side air bag/pretensioner connector.
13. WARNING: The restraint system diagnostic tool is for restraint system service only. Remove from the vehicle prior to road use. Failure to follow this instruction may result in personal injury and possible violation of vehicle safety standards.
Make sure all restraint system diagnostic tool(s) that have been installed during the repair have been removed from the vehicle and all SRS components are connected.
14. Turn the ignition switch from OFF to ON.
15. Install the RCM fuse F60 (7.5A) to the CJB and install the cover.
16. WARNING: Make sure that nobody is in the vehicle and that there is nothing blocking or set in front of any air bag module when the battery ground cable is connected. Failure to follow this instruction may result in personal injury.
Connect the battery ground cable.
17. Prove out the supplemental restraint system (SRS) as follows:
Turn the ignition key from ON to OFF. Wait 10 seconds, then turn the key back to ON and visually monitor the air bag indicator with the air bag modules installed. The air bag indicator will light continuously for approximately six seconds and then turn off. If an SRS fault is present, the air bad indicator will either:
- fail to light.
- remain lit continuously.
- flash.
The flashing might not occur until approximately 30 seconds after the ignition switch has been turned from the OFF to the ON position. This is the time required the restraints control module (RCM) to complete the testing of the SRS. If the air bag indicator is inoperative and an SRS fault exists, a chime will sound in a pattern of five sets of five beeps. If this occurs, the air bag indicator and any SRS fault discovered must be diagnosed and repaired.
Clear all continuous DTCs from the restraints control module using a scan tool.