Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using the 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 B0085 01: Left Front Side Impact Sensor Short to BatteryDTC B0085 02: Left Front Side Impact Sensor Short to Ground
DTC B0085 04: Left Front Side Impact Sensor Open Circuit
DTC B0085 0F: Left Front Side Impact Sensor Erratic
DTC B0085 39: Left Front Side Impact Sensor Internal Electronic Failure
DTC B0085 3A: Left Front Side Impact Sensor Incorrect Component Installed
DTC B0085 71: Left Front Side Impact Sensor Invalid Serial Data Received
DTC B0086 01: Right Front Side Impact Sensor Short to Battery
DTC B0086 02: Right Front Side Impact Sensor Short to Ground
DTC B0086 04: Right Front Side Impact Sensor Open Circuit
DTC B0086 0F: Right Front Side Impact Sensor Erratic
DTC B0086 39: Right Front Side Impact Sensor Internal Electronic Failure
DTC B0086 3A: Right Front Side Impact Sensor Incorrect Component Installed
DTC B0086 71: Right Front Side Impact Sensor Invalid Serial Data Received
Circuit/System Description
The inflatable restraint side impact sensor (SIS) utilizes a bi-directional 2-wire circuit. The SIS 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 SIS. When the ignition is turned ON and input power from the SDM is first detected, the SIS 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 SIS continually communicates status messages to the SDM, which determines if a fault is present in the SIS circuit. When a fault is detected, the SDM resets the SIS twice 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
B0085 01 or B0086 01
| • | The SIS has been shorted to voltage. |
| • | The SDM has not received a message from the SIS for more than 375 milliseconds. |
B0085 02 or B0086 02
| • | The SIS has been shorted to ground. |
| • | The SDM current has been above 23 mA. |
B0085 04 or B0086 04
The side impact sensor circuit is open.
B0085 0F or B0086 0F
The SDM has received erratic messages from the SIS.
B0085 39 or B0086 39
| • | The SDM has received a NOK message from the SIS. |
| • | The SDM has not received a message. |
B0085 3A or B0086 3A
| • | The SDM has received an ID message from the SIS which does not match the ID stored in the SDM memory. |
| • | The SDM has reset the SIS twice without detecting the correct ID message. |
B0085 71 or B0086 71
The SDM has received erratic messages from the SIS.
Action Taken When the DTC Sets
| • | The SDM commands the AIR BAG indicator ON via serial data communications. |
| • | The side SIR System is disabled and no side deployments are allowed. Frontal deployments and rollover detection are still enabled. |
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. |
Reference Information
Schematic Reference
Connector End View Reference
Electrical Information Reference
Circuit/System Testing
- Ignition OFF, if DTC B0085 is current, disconnect the LF SIS connector. If DTC B0086 is current, disconnect the RF SIS connector.
- Remove the harness connector at the SDM.
- Ignition ON, test the signal and voltage circuits between the SDM and SIS harness connectors for a short to voltage, short to ground, or open/low resistance. Verify that a short to voltage, short to ground, or open/low resistance does not exist.
- Ignition OFF, reconnect all SIR components
- Ignition ON, use the scan tool to clear the DTCs then recheck for DTCs.
Important: When removing connectors, inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the affected component/connector:
• The SIS • The SDM module • The SIS wiring harness connector • The SDM wiring harness connector
| ⇒ | If any of the above conditions are found, make the appropriate repair. |
| ⇒ | If DTC B0085 sets as current, replace the LF SIS. If DTC B0086 sets as current, replace the RF SIS. After replacement, refer to Repair Verification. |
Repair Instructions
| • | Control Module References for SDM replacement, setup, and programming |
Repair Verification
Ignition ON, use the scan tool to clear the DTCs then recheck for DTCs.
| ⇒ | If DTC B0085 or B0086 was current, replace the SDM. |
