GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2005 🢒 Cobalt 🢒 Restraints 🢒 SIR 🢒 DTC B0083

Circuit Description

The inflatable restraint front end sensor also known as the electronic frontal sensor (EFS) utilizes a unidirectional 2-wire circuit. The front end sensor modulates current on the interface to send ID, State of Health (SOH), and deployment commands to the inflatable restraint sensing and diagnostic module (SDM). The SDM serves as a power source and a ground for the front end sensor. When the ignition is turned ON and input power from the SDM is first detected, the front end sensor responds by performing internal diagnostics and sending an ID to the SDM. The SDM considers the ID to be valid if the response time is less than 5 seconds. The front end sensor continually communicates status messages to the SDM, which determines if a fault is present in the front end sensor circuit. When a fault is detected, the SDM may reset the front end sensor up to 2 times by removing and reapplying power to it. If the fault is still present, the SDM will set a diagnostic trouble code (DTC).

DTC Descriptors

This diagnostic procedure supports the following DTC:

DTC B0083 Front End Sensor 1

DTC Symptom

DTC Symptom Descriptor

01

Front End Sensor Short To Battery

02

Front End Sensor Short To Ground

04

Front End Sensor Open Circuit

39

Front End Sensor Internal Electronic Failure

71

Front End Sensor Invalid Serial Data Received

0F

Front End Sensor Erratic

3A

Front End Sensor Incorrect Component Installed

Conditions for Running the DTC

Ignition 1 voltage is within the normal operating voltage range of 9-16 volts.

Conditions for Setting the DTC

All of the following conditions exist for 2.5 seconds:

B0083 01

    • The front end sensor has been shorted to voltage.
    • The SDM has not received a message from the front end sensor for more than 375 milliseconds.

B0083 02

    • The front end sensor has been shorted to ground.
    • The front end sensor current has been above 23 mA for longer than 5 milliseconds.

B0083 04

The front end sensor circuit is open.

B0083 39

    • The SDM has received a NOK message from the front end sensor.
    • The SDM has not received a message.

B0083 71

The SDM has received invalid serial data from the front end sensor.

B0083 0F

The SDM has received erratic messages from the front end sensor.

B0083 3A

    • The SDM has received an ID message from the front end sensor which does not match the ID stored in the SDM memory.
    • The SDM has reset the front end sensor twice without detecting the correct ID message.

Action Taken When the DTC Sets

The SDM commands ON the AIR BAG warning lamp via GMLAN serial data.

Conditions for Clearing the MIL/DTC
    • The DTC will clear when 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

The following are conditions that may cause the malfunction:

    • An open in the front end sensor circuit
    • A short to ground or voltage in the front end sensor circuit
    • High or low resistance in the front end sensor circuit
    • Improper front end sensor installed on vehicle
    • An internal failure in the front end sensor

Thoroughly inspect the wiring and the connectors. An incomplete inspection of the wiring and connectors may result in misdiagnosis, causing a part replacement with the reappearance of the malfunction. If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections .

Test Description

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

  1. This step tests the front end sensor signal and front end sensor voltage circuits for high or low resistance or open

    2.

  2. This step tests between the front end sensor signal and front end sensor voltage circuits for continuity

    3.

  3. This step tests the front end sensor signal and front end sensor voltage circuits for a short to voltage or ground.

Step

Action

Yes

No

Schematic Reference: SIR Schematics

Connector End View Reference: SIR Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

    Important: J-45289 CANdi module must be used with the scan tool.

  1. Install a scan tool, request the SIR DTC display.
  2. Turn ON the ignition, with the engine OFF.

Does the scan tool indicate that DTC B0083 is current?

Go to Step 3

Go to Testing for Intermittent Conditions and Poor Connections

3

  1. Turn OFF the ignition.
  2. If DTC B0083 is current, disconnect the front end sensor 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 .

Does the connector exhibit any signs of damage or corrosion?

Go to Step 4

Go to Step 5

4
  1. If the component side of the front end sensor connector is damaged, the front end 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 complete the repair?

Go to Step 11

--

5
  1. Turn OFF the ignition.
  2. Disconnect the inflatable restraint sensing and diagnostic module (SDM) connector. Refer to Control Module References for replacement, setup, and programming.
  3. Inspect both the component and harness sides of the SDM connector for damage or corrosion. Refer to Testing for Intermittent Conditions and Poor Connections .

Does the connector exhibit any signs of damage or corrosion?

Go to Step 6

Go to Step 7

6
  1. If the component side of the SDM connector is damaged, the SDM must be replaced. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.
  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 repair?

Go to Step 11

--

7

  1. If DTC B0083 is current, disconnect the front end sensor connector.
  2. Test both the front end sensor signal and voltage circuits for high or low resistance or an open between the SDM connector and the front end sensor connector. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 11

Go to Step 8

8

Test for continuity between the front end sensor signal and voltage circuits on the SDM connector. Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 11

Go to Step 9

9

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

Did you find and correct the condition?

Go to Step 11

Go to Step 10

10
  1. Turn OFF the ignition.
  2. If DTC B0083 was current replace the front end sensor. Refer to Inflatable Restraint Front End Sensor Replacement .

Did you complete the replacement?

Go to Step 11

--

11
  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 12

System OK

12
  1. Turn OFF the ignition.
  2. Replace the SDM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 13

--

13
  1. Turn ON the ignition, with the engine OFF.
  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 2

System OK