GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2002 🢒 Escalade 🢒 Body and Accessories 🢒 Wiring Systems 🢒 Diagnostic System Check - SIR

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.

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:
    2. • 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.

Test Description

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.

  2. This step checks to see if the scan tool powers up.

    3.

  3. This step checks to see if the scan tool can communicate with the SDM.

    4.

  4. This step checks to see if there are any current or history DTCs present.

    5.

  5. This step checks to see if there are communication DTCs, U-codes, present.

    6.

  6. This step checks to see if DTC B1000 is present.

Step

Action

Yes

No

1

Note the AIR BAG indicator while turning the ignition switch ON.

Does the AIR BAG indicator flash 7 times?

Go to Step 2

Go to Symptoms - SIR

2

Install a scan tool.

Does the scan tool power up?

Go to Step 3

Go to Scan Tool Does Not Power Up in Data Link Communications

3

Attempt to establish communication with the SDM.

Does the scan tool communicate with the SDM?

Go to Step 4

Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications

4

  1. With a scan tool, request the SIR DTC display.
  2. Record the displayed DTCs on the repair order, specifying as current or history.

Does the scan tool display any current or history DTCs?

Go to Step 5

System OK

5

Does the scan tool display any DTCs which begin with a "U"?

Go to Diagnostic Trouble Code (DTC) List in Data Link Communications

Go to Step 6

6

Does the scan tool display DTC B1000?

Go to DTC B1000 in Body Control System

Go to Diagnostic Trouble Code (DTC) List