SRS Diagnostic System Check

Caution: In order to avoid deploying the air bag when troubleshooting the Supplemental Restraint System (SRS), use only the equipment specified and the instructions given. Failure to use the specified equipment as instructed could cause air bag deployment, personal injury to you or someone else, or unnecessary SRS repairs.

Caution: Be careful when you handle a Sensing and Diagnostic Module (SDM). Do not strike or jolt the 8DM. Before applying power to the SDM:
- Remove any did, grease, etc. from the mounting surface
- Position the SDM horizontally on the mounting surface
- Point the arrow on the SDM toward the front of the vehicle
- Tighten all of the SDM fasteners and SDM bracket fasteners to the specified torque value

Failure to follow the correct procedure could cause air bag deployment, personal injury, or unnecessary Supplemental Restraint System repairs.

These diagnostic procedures will help you to find and repair SRS malfunctions. This service category also contains information for repairing SRS malfunctions. For best results, use the diagnostic tables, and follow the sequence listed below:

1. Perform the SRS Diagnostic System Check. All SRS diagnostics must begin with the SRS Diagnostic System Check. The SRS Diagnostic System Check determines the following:
- Proper AIR BAG warning lamp operation.
- Ability of the SDM to communicate through the Data Link Connector (DLC).
- Existence of SRS Diagnostic Trouble Codes. (DTC).

2. Refer to the diagnostic table as directed by the SRS Diagnostic System Check. The diagnostic tables will help enable you to diagnose any SRS malfunction. Bypassing these procedures may result in the following:
- Extended Diagnostic Time.
- Incorrect Diagnosis.
- Incorrect Pants Replacement.

3. Repeat the SRS Diagnostic System Check after you perform any repair or diagnostic procedures. This will verify that you correctly performed the repair. This will also ensure that no other malfunctions exist.

Circuit Description
The ignition switch supplies Ignition 1 voltage to the supplemental restraint Sensing and Diagnostic Module (SDM) at terminal 10 using the SIR Fuse. When the ignition switch is first turned to the RUN position, the SDM responds by flashing the AIR BAG warning lamp seven times, then turning it OFF, while performing tests on the SRS.

Diagnostic Aids
You must diagnose the diagnostic trouble codes in the order specified by the SRS Diagnostic System Check. Failure to do so may result in the following:
- Extended Diagnostic Time.
- Incorrect Diagnosis.
- Incorrect Parts Replacement.

SRS Diagnostic System Check (Part 1 0f 2):

SRS Diagnostic System Check (Part 2 0f 2):

Test Description
Refer to step numbers on the diagnostic table.

2. The supplemental restraint IP module switch must be in the ON position to perform the system diagnostic check.
3. The AIR BAG warning lamp should flash seven times after the ignition switch is first turned to the RUN position.
4. The AIR BAG warning lamp indicates improper operation. This test differentiates a warning lamp stays ON condition from a warning lamp does not come ON condition.
5. The AIR BAG warning lamp should turn OFF after flashing seven times.
6. This test checks for the proper operation of the Serial Data line.
8. This test will identify the stored diagnostic trouble codes and whether they are current or history.
10. This test checks for the proper operation of the Serial Data line.
11. This test refers to the appropriate DTC Table Diagnostic Aids for diagnosis of the history DTCs.