• | 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 |
---|---|---|---|---|---|
Ignition 1 | B0090 0F | B0090 0F | B0090 0F | -- | B0090 0F |
Roll Over Sensor Signal | B0090 0F | B0090 0F | B0090 0F | B0090 0F | B0090 0F |
Roll Over Sensor Ground | -- | B0090 0F | B0090 0F | -- | B0090 0F |
The inflatable restraint vehicle rollover sensor (ROS) utilizes ignition 1 voltage supply and a bidirectional interface circuit. The ROS modulates current on the interface to send ID, state of health, and deployment commands to the inflatable restraint sensing and diagnostic module (SDM). When the ignition is turned on the ROS responds by performing internal diagnostics and sending an ID to the SDM. The ROS continually communicates status messages to the SDM, which determines if a fault is present in the ROS circuit. If the fault is present, the SDM will set a diagnostic trouble code (DTC).
Ignition voltage is between 9-16 volts.
Any of the following conditions must exist for 5 seconds:
• | The SDM received a fault present message from the ROS. |
• | The ROS is in assembly plant mode and the SDM is in production mode. |
• | The SDM has not received any data from the ROS. |
• | The SDM has received an ID message from the vehicle rollover sensor which does not match the ID stored in the SDM memory. |
• | The SDM has reset the vehicle rollover sensor twice without detecting the correct ID message. |
The SDM has received invalid serial data from the vehicle rollover sensor.
• | The SDM requests the instrument panel cluster (IPC) to illuminate the AIR BAG indicator. |
• | The side air bag deployment loops will be disabled for rollover events only. For side impact events the side air bags are still enabled. |
• | The condition for setting the DTC no longer exists. |
• | A history DTC will clear once 100 malfunction-free ignition cycles have occurred. |
If either the SDM or vehicle rollover sensor were replaced verify that the correct part numbers were used for the vehicle application and the components were properly configured. Refer to Control Module References for SDM and ROS setup and programming.
SIR System Description and Operation
Control Module References for scan tool information
Important: Refer to SIR Service Precautions.
Important: When removing connectors inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the affected component/connector.
• Vehicle rollover sensor • SDM module • Vehicle rollover sensor harness connector • SDM wiring harness connector
⇒ | If greater then the specified range, test the ground circuit for an open/high resistance. |
⇒ | If less than the specified range, test the serial data circuit for a short to ground. |
⇒ | If greater then the specified range, test the serial data circuit for a short to voltage. |
⇒ | If greater then the specified range, test the serial data circuit for an open/high resistance. |
⇒ | If the test lamp does not illuminate, test the ignition circuit for an open/high resistance. If the circuit fuse is open, test the circuit for a short to ground, if the circuit tests normal, replace the rollover sensor. |
⇒ | If the DTC is set, replace the SDM. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for SDM and ROS replacement, setup, and programming |