GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2005 🢒 Vivant 🢒 Body 🢒 Data Link Communications 🢒 Diagnostic System Check - SIR

The Diagnostic System Check must always be the starting point for any SIR diagnosis. The Diagnostic System Check-SIR reveals diagnostic trouble codes (DTCs) through the use of a scan tool.

The diagnostic procedures used in this section are designed to find and repair SIR conditions. To get the best results, it is important to use the diagnostic charts and follow the sequence listed below.

  1. Perform the Diagnostic System Check - SIR, which reveals diagnostic trouble codes (DTCs) through the use of a scan tool. It also check for proper AIRBAG indicator operation.
  2. Refer to the proper diagnostic chart as directed by the Diagnostic System Check - SIR. Bypassing these procedures may result in extended diagnostic time, incorrect diagnosis, and incorrect parts replacement.
  3. Repeat the Diagnostic System Check - SIR after any repair or diagnostic procedures have been performed to ensure that the repair has been made correctly and that no other malfunction exists.

Circuit Description

When the ignitions switch is first turned to ON, ignition voltage is supplied from airbag fuse to the SDM at input terminal A1. The SDM responds by flashing the AIRBAG indicator seven times and then turning it off while the SDM performs tests on the SRS.

Diagnostic Aids

The order in which DTCs are diagnosed is very important. Failure to diagnose the DTCs in the order specified may result in extended diagnostic time, incorrect diagnosis, and incorrect parts replacement.

Diagnostic System Check - SIR

Caution: Refer to Sensing and Diagnostic Module Voltage after Ignition is Turned Off Caution in the Preface section.

Caution: Refer to Sensing and Diagnostic Module Handling Caution in the Preface section.

Step

Action

Yes

No

1
  1. Turn ON the ignition switch.
  2. Observe the AIRBAG indicator as the ignition is being turned ON.

Does the indicator flash seven times?

Go to Step 2

Go to Step 6

2

Observe the AIRBAG indicator after the ignition has been turned ON.

Does the AIRBAG indicator turn OFF?

Go to Step 10

Go to Step 3

3
  1. Turn OFF the ignition and remove the key.
  2. Connect the scan tool to the data link connector (DLC). Follow the directions given in the scan tool manual.
  3. Turn ON the ignition.
  4. Request the DTC display with the scan tool.
  5. Record all DTCs, indicating each as either a current or a history DTC.

Are only history DTCs displayed?

Refer to Diagnostic Trouble Code (DTC) List

Go to Step 4

4

Check the recorded DTCs.

Are current DTCs 18, 24, 51, or 53 set?

Go to The appropriate DTC for Diagnosis

Go to Step 5

5

Check the recorded DTCs.

Are there any other current DTCs shown?

Diagnose the remaining current DTCs from the lowest number to the highest

Refer to Diagnostic Trouble Code (DTC) List

6

Observe the AIRBAG indicator after the ignition has been turned ON.

Does the AIRBAG indicator stay on?

Go to Air Bag Indicator Always On

Go to Step 7

7
  1. Turn OFF the ignition and remove the key.
  2. Disconnect the sensing and diagnostic module (SDM) connector.
  3. Check the AIRBAG indicator bulb and circuit.

Are the bulb and bulb circuit in good condition?

Go to Step 9

Go to Step 8

8
  1. Replace the bulb or repair the bulb circuit.
  2. Connect the SDM connector and ensure that all components are properly mounted.

Did you complete the repair?

Go to Step 1

--

9
  1. Turn OFF the ignition and remove the key.
  2. Disable the SIR. Refer to Disabling the SIR System .
  3. Replace the SDM. The arrow on the SDM must be pointing toward the front of the vehicle.
  4. Enable the SIR and ensure that all components are properly mounted.

Did you complete the repair?

Go to Step 1

--

10
  1. Turn OFF the ignition and remove the key.
  2. Connect the scan tool to DLC. Follow the direction given in the scan tool manual.
  3. TurnON the ignition switch.
  4. Request all history DTCs.

Are any DTCs displayed?

Go to Step 11

System OK

11

Turn OFF the ignition.

Is the DTC 71 set?

Go to DTC 71 DTC 071

Refer to Diagnostic Trouble Code (DTC) List