GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2003 🢒 Cavalier 🢒 DTC 🢒 DTC B0036

Circuit Description

The inflatable restraint sensing and diagnostic module (SDM) monitors the inflatable restraint front end sensor circuit for front impact detection. The SDM processes the signal provided by the front end sensor to further support deployment of the air bags. The front end sensor is an input only to the SDM and does not directly cause air bag deployment. When the ignition is turned ON, the SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. If a malfunction is detected, a diagnostic trouble code (DTC) will be stored.

Conditions for Running the DTC

Ignition 1 voltage is within the normal operating voltage range.

Conditions for Setting the DTC

The SDM detects the voltage at the front end sensor signal is greater than 3.65 volts for 300 milliseconds.

Action Taken When the DTC Sets

The SDM commands ON the AIR BAG indicator via class 2 serial data.

Conditions for Clearing the DTC
    • The condition responsible for setting the DTC no longer exists, and the scan tool clear DTCs function is used.
    • A history DTC will clear once 255 malfunction free ignition cycles have occurred.

Diagnostic Aids

A broken or chafed wire in the front end sensor circuit may cause an intermittent condition to occur. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step test both front end sensor voltage and ground circuits for an open or high resistance.

    2.

  2. This step test both front end sensor voltage and ground circuits for a short to battery.

Step

Action

Yes

No

Schematic Reference: SIR Schematics

Connector End View Reference: SIR Connector End Views

1

Did you perform the Diagnostic System Check - SIR?

Go to Step 2

Go to Diagnostic System Check - SIR

2
  1. Turn OFF the ignition.
  2. Disconnect the front end sensor in-line connector. Refer to Inflatable Restraint Front End Sensor Replacement .
  3. Inspect both the component and harness sides of the connector for damage or corrosion. Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 3

3
  1. If the component side of the front end sensor connector is damaged, the sensor must be replaced. Refer to Inflatable Restraint Front End Sensor Replacement .
  2. If the harness side of the front end sensor connector is damaged, replace the harness side of the connector. Refer to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 4

4
  1. Disconnect the inflatable restraint sensing and diagnostic module (SDM) connector. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement .
  2. Inspect both the component and harness sides of the SDM connector for damage or corrosion. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Does the connector exhibit any signs of damage or corrosion?

Go to Step 5

Go to Step 6

5

  1. If the component side of the SDM connector is damaged, the SDM must be replaced. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement .
  2. If the harness side of the SDM connector is damaged, replace the harness side of the connector. Refer to Connector Repairs in Wiring Systems.

Did you complete the replacement?

Go to Step 9

--

6

Test both front end sensor voltage and ground circuits for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 7

7

  1. Turn ON the ignition, with the engine OFF.
  2. Test both front end sensor voltage and ground circuits for a short to battery. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 9

Go to Step 8

8

Replace the front end sensor. Refer to Inflatable Restraint Front End Sensor Replacement .

Did you complete the replacement?

Go to Step 9

--

9
  1. Reconnect all SIR components.
  2. Use the scan tool in order to Clear the DTCs.
  3. Operate the vehicle within the Conditions for Running the DTC as specified in the text.

Does the DTC reset?

Go to Step 10

System OK

10
  1. Turn OFF the ignition.
  2. Replace the SDM. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement .

Did you complete the replacement?

Go to Step 11

--

11
  1. Verify that all components, connectors, and CPAs are properly mounted.
  2. Turn ON the ignition, with the engine OFF.
  3. Use the scan tool in order to Clear the DTCs.
  4. Operate the vehicle within the Conditions for Running the DTC as specified in the text.

Does the DTC reset?

Go to Step 2

System OK