B0086
DTC B0085 or B0086
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) provides an overview of each diagnostic category.
DTC Descriptors
DTC B0085 01
- Left Front Side Impact Sensor Short to Battery
DTC B0085 02
- Left Front Side Impact Sensor Short to Ground
DTC B0085 0F
- Left Front Side Impact Sensor Erratic Serial Data Received
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 0F
- Right Front Side Impact Sensor Erratic Serial Data Received
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
Diagnostic Fault Information
Circuit/System Description
The side impact sensor utilizes a 2-wire circuit. The side impact sensor receives 25 volts from the inflatable restraint sensing and diagnostic module (SDM). The side impact sensor modulates the voltage in order to send ID, state of health, and deployment commands to the SDM. When the ignition is turned ON and input power from the SDM is first detected, the side impact 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 side impact 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 side impact sensor up to 2 times by removing and reapplying power to it. If the fault is still present, DTC B0085 or B0086 and the appropriate symptom byte sets.
Conditions for Running the DTC
Ignition voltage is between 9-16 volts.
Conditions for Setting the DTC
All of the following conditions exist for 2.5 seconds:
B0085 01 or B0086 01
* The side impact sensor signal circuit voltage is greater than the expected value.
* The SDM did not receive a message from the side impact sensor for more than 375 milliseconds
B0085 02 or B0086 02
* The side impact sensor signal circuit is shorted to ground.
* The side impact sensor current is greater than 23 mA for greater than 5 milliseconds.
B0085 0F or B0086 0F
The SDM received erratic messages from the side impact sensor.
B0085 39 or B0086 39
The SDM received a NOK message from the side impact sensor.
B0085 3A or B0086 3A
* The SDM received an ID message from the side impact sensor that does not match the ID stored in the SDM memory.
* The SDM has reset the side impact sensor twice without detecting the correct ID message.
B0085 71 or B0086 71
The SDM received invalid serial data from the side impact sensor.
Action Taken When the DTC Sets
* The SDM requests the instrument panel cluster (IPC) to illuminate the AIR BAG indicator and display the message "Service Air Bag".
* The 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 ([1][2]Air Bag Systems)
Connector End View Reference
Component Connector End Views (Connector End Views By Name)
Description and Operation
SIR System Description and Operation (SIR System)
Electrical Information Reference
* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Circuit/System Testing
Important: Refer to SIR Service Precautions (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:
* Side impact sensor
* SDM
* Side Impact Sensor wiring harness connector
* The SDM wiring harness connector
1. Ignition OFF, disconnect the harness connector at the SDM and the appropriate side impact sensor.
2. Ignition ON, test for less than 1-volt between the side impact sensor circuit terminals listed below and ground:
* Side impact sensor low reference circuit terminal A and ground.
* Side impact sensor signal circuit terminal B and ground.
3. Test for infinite resistance between the side impact sensor voltage circuit terminal B and ground.
• If less than the specified value, test the voltage circuit for a short to ground.
4. Test for less than 1 ohm between the side impact sensor circuit terminals listed below:
* Right front side impact sensor terminal A and SDM harness connector terminal 48
* Right front side impact sensor terminal B and SDM harness connector terminal 49.
* Left front side impact sensor terminal A and SDM harness connector terminal 47.
* Left front side impact sensor terminal B and SDM harness connector terminal 46.
• If greater than the specified range, test the circuit for an open/voltage resistance.
5. If all circuits test normal, replace the appropriate side impact sensor.
6. Reconnect all SIR components. Ignition ON, verify the DTC does not set as current.
• If the DTC resets as current, replace the SDM.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Inflatable Restraint Side Impact Sensor Replacement (Inflatable Restraint Side Impact Sensor Replacement)
* SIR/SRS Wiring Repairs (SIR/SRS Wiring Repairs)
* Control Module References (Programming and Relearning) for SDM replacement, setup, and programming