• | 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. |
Circuit | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance |
---|---|---|---|---|---|
Side Impact Sensor LF Signal Circuit | -- | B0085 00 | B0085 00 | B0085 00 | B0085 0F |
Side Impact Sensor LF Voltage | B0085 00 | B0085 00 | B0085 00 | -- | B0085 0F |
Side Impact Sensor RF Signal Circuit | -- | -- | B0086 04 | -- | B0086 0F |
Side Impact Sensor RF Voltage | B0086 00 | B0086 00 | B0086 00 | -- | B0086 0F |
The inflatable restraint side impact sensor (SIS) utilizes a unidirectional 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.
Ignition voltage is between 9-16 volts.
All of the following conditions exist for 2.5 seconds:
• | The SIS has been shorted to ground. |
• | The SIS current has been above 23 mA for longer than 5 milliseconds. |
• | The SIS has been shorted to voltage. |
• | The SIS circuit is open. |
• | The SDM has not received a message from the SIS for more than 375 milliseconds. |
The SDM has received erratic messages from the SIS.
• | The SDM has received a NOK message from the SIS. |
• | The SDM has not received a message. |
• | 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. |
The SDM has received invalid serial data from the SIS.
• | The SDM commands the AIR BAG indicator ON via serial data communications. |
• | The SIR System is disabled and no deployments are allowed. |
• | 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. |
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 is current, replace the LF SIS. If DTC B0086 is current, replace the RF SIS. After replacement, clear and recheck for DTCs if DTC B0085 or DTC B0086 are still current, replace the SDM. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for SDM replacement, setup, and programming |