For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### DTC Descriptors

DTC B0083 01: Electronic Front End Sensor 1 Short to Battery
DTC B0083 02: Electronic Front End Sensor 1 Short to Ground
DTC B0083 04: Electronic Front End Sensor 1 Open Circuit
DTC B0083 0F: Electronic Front End Sensor 1 Erratic
DTC B0083 39: Electronic Front End Sensor 1 Internal Electronic Failure
DTC B0083 3A: Electronic Front End Sensor 1 Incorrect Component Installed
DTC B0083 71: Electronic Front End Sensor 1 Invalid Serial Data Received
DTC B0085 01: LF Side Impact Sensor Short to Battery
DTC B0085 02: LF Side Impact Sensor Short to Ground
DTC B0085 04: LF Side Impact Sensor Open Circuit
DTC B0085 0F: LF Side Impact Sensor Erratic
DTC B0085 39: LF Side Impact Sensor Internal Electronic Failure
DTC B0085 3A: LF Side Impact Sensor Incorrect Component Installed
DTC B0085 71: LF Side Impact Sensor Invalid Serial Data Received
DTC B0086 01: RF Side Impact Sensor Short to Battery
DTC B0086 02: RF Side Impact Sensor Short to Ground
DTC B0086 04: RF Side Impact Sensor Open Circuit
DTC B0086 0F: RF Side Impact Sensor Erratic
DTC B0086 39: RF Side Impact Sensor Internal Electronic Failure
DTC B0086 3A: RF Side Impact Sensor Incorrect Component Installed
DTC B0086 71: RF Side Impact Sensor Invalid Serial Data Received

### Diagnostic Fault Information

Circuit | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance
--- | --- | --- | --- | --- | ---
Front End Sensor 1 High | B0083 02 | B0083 0F | B0083 04 | B0083 01 | B0083 0F
Front End Sensor 1 Low | B0083 02 | B0083 0F | B0083 04 | B0083 01 | B0083 0F
Left Front Side Impact Sensor High | B0085 02 | B0085 0F | B0085 04 | B0085 01 | B0085 0F
Left Front Side Impact Low | B0085 02 | B0085 0F | B0085 04 | B0085 01 | B0085 0F
Right Front Side Impact Sensor High | B0086 02 | B0086 0F | B0086 04 | B0086 01 | B0086 0F
Right Front Side Impact Low | B0086 02 | B0086 0F | B0086 04 | B0086 01 | B0086 0F

### Circuit/System Description

The inflatable restraint front end sensor utilizes a bidirectional 2-wire circuit. The sensor modulates current on the interface to send ID, state of health, and deployment commands to the inflatable restraint sensing and diagnostic module (SDM). The SDM serves as a power source and a ground for the sensor. When the ignition is turned ON and input power from the SDM is first detected, the 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 sensor circuit. When a fault is detected, the SDM may reset the sensor up to 2 times by removing and reapplying power to it. If the fault is still present, the SDM will set a DTC.

### Conditions for Running the DTC

Ignition voltage is between 9-16 volts.

### Conditions for Setting the DTC

Any of the following conditions exist for 2.5 seconds:

#### B0083 01, B0085 01, B0086 01

The front end sensor has been shorted to voltage.

#### B0083 02, B0085 02, B0086 02

• | The sensor has been shorted to ground.

• | The sensor current is greater than 23 mA for greater than 375 milliseconds.

#### B0083 04, B0085 04, B0086 04

• | The sensor circuit is open.

• | The SDM has not received a message from the sensor for greater than 375 milliseconds.

#### B0083 0F, B0085 0F, B0086 0F

The SDM has received erratic messages from the sensor.

#### B0083 39, B0085 39, B0086 39

• | The SDM has received a Not OK (NOK) message from the sensor.

• | The SDM has not received a message.

#### B0083 3A, B0085 3A, B0086 3A

• | The SDM has received an ID message from the sensor, which does not match the ID stored in the SDM memory.

• | The SDM has reset the sensor twice without detecting the correct ID message.

#### B0083 71, B0085 71, B0086 71

The SDM has received invalid serial data from the sensor.

### Action Taken When the DTC Sets

• | The SDM requests the instrument panel cluster (IPC) to illuminate the AIR BAG warning indicator.

• | The supplemental inflatable restraints (SIR) system is disabled and no deployments are allowed.

### Conditions for Clearing the DTC

• | The condition for setting the DTC no longer exists.

• | A history DTC will clear once 100 malfunction-free ignition cycles have occurred.

### Reference Information

#### Schematic Reference

SIR Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

SIR System Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Testing for Intermittent Conditions and Poor Connections

• | Connector Repairs

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Testing

Important: Refer to SIR Service Precautions.

When removing connectors, inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the affected component/connector:

• | Front end sensor

• | SDM module

• | Front end sensor wiring harness connector

• | SDM wiring harness connector

1. Ignition OFF, disconnect the harness connector at the SDM and the appropriate sensor.
2. Ignition ON, test for less than 1 volt between the signal circuit terminal B and ground.

⇒ | If greater than the specified range, test the circuit for a short to voltage.

3. Ignition ON, test for less than 1 volt between the low reference circuit terminal A and ground.

⇒ | If greater than the specified range, test the circuit for a short to voltage.

4. Test for infinite resistance between the signal circuit terminal B and ground.

⇒ | If less than infinite resistance, test the circuit for a short to ground.

5. Test for less than 1 ohm between the following signal circuit terminals listed below:

• | Front end sensor terminal B and SDM harness connector terminal 38.

• | Right front side impact sensor terminal B and the SDM harness connector terminal 49.

• | Left front side impact sensor terminal B and the SDM harness connector terminal 46.

⇒ | If greater than the specified range, test the circuit for an open/high resistance.

6. Test for less than 1 ohm between the following front end sensor low reference circuit terminals listed below:

• | Front end sensor terminal A and SDM harness connector terminal 39.

• | Right front side impact sensor terminal A and the SDM harness connector terminal 48.

• | Left front side impact sensor terminal A and the SDM harness connector terminal 47.

⇒ | If greater than the specified range, test the circuit for an open/high resistance.

7. If all circuits test normal, replace the appropriate sensor.
8. Reconnect all SIR components. Ignition ON, with a scan tool clear and check for DTCs.

⇒ | If the DTC returns and is current, replace the SDM.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Inflatable Restraint Front End Sensor Replacement

• | Inflatable Restraint Side Impact Sensor Replacement

• | SIR/SRS Wiring Repairs

• | Control Module References for SDM replacement, setup, and programming