Diagnostic System Check

CAUTION:
^ In order to avoid deploying the air bag when troubleshooting the SIR system, use only the equipment specified in this manual and the instructions given in this manual. Failure to use the specified equipment as instructed could cause air bag deployment, personal injury to you or someone else, or unnecessary SIR system repairs.
^ If any water enters the vehicle's interior up to the level of the carpet or higher and soaks the carpet, the sensing and diagnostic module (SDM) and the SDM harness connector may need to be replaced. The SDM could be activated when powered, which could cause deployment of the air bag(s) and result in personal injury. Before attempting these procedures, the SIR system must be disabled. Refer to Disabling the SIR System.

With the ignition OFF, inspect the SDM mounting area, including the carpet. If any significant soaking or evidence of significant soaking is detected, you must perform the following tasks:
1. Remove all water.
2. Repair the water damage.
3. Replace the SDM harness connector.
4. Replace the SDM.

Failure to follow these tasks could result in possible air bag deployment, personal injury, or otherwise unneeded SIR system repairs.

These diagnostic procedures will help you find and repair SIR system malfunctions. For best results, use the diagnostic tables and follow the sequence listed below:
1. Refer to the diagnostic tables as directed by the Diagnostic System Check - SIR. The diagnostic tables will assist you in diagnosing SIR system malfunctions. Bypassing these procedures may result in the following:
^ Extended diagnostic time
^ Incorrect diagnosis
^ Incorrect parts replacement
2. Repeat the Diagnostic System Check - SIR after you perform any repairs or diagnostic procedures. This will verify that you correctly performed the repair. This will also verify that no other SIR system malfunctions exist.

Circuit
For the circuit schematics refer to Diagrams/Electrical.

TEST DESCRIPTION

Steps 1-6:

The numbers below refer to the step numbers on the diagnostic table.
1. This step checks to see if the AIR BAG indicator flashes seven times when the ignition switch is first turned ON.
2. This step checks to see if the scan tool powers up.
3. This step checks to see if the scan tool can communicate with the SDM.
4. This step checks to see if there are any current or history DTCs present.
5. This step checks to see if there are communication DTCs (U-codes) present.
6. This step checks to see if DTC B1000 is present.