Circuit Description
When you first turn ON the ignition, the inflatable restraint sensing and diagnostic module (SDM) performs tests to diagnose critical malfunctions within itself. The SDM provides input power to the inflatable restraint side impact sensor (SIS). When input power is first detected, the SIS responds by performing internal diagnostics. Next the SIS sends an ID message to the SDM. The SDM will consider this to be a valid ID if the response time is less than 5 seconds after the SIS is powered up. The SIS will continually communicate a status message to the SDM. The SDM can reset the SIS by removing and applying power to it.
Conditions for Running the DTC
The SDM monitors the LF SIS loop with power on.
| • | The SIS will send an ID message to the SDM. |
| • | The SIS will continuously send OK or NOK message to SDM. |
Conditions for Setting the DTC
| • | The ignition is within normal operating voltage range. |
| • | The SDM has received an ID message from the LF SIS which does not match the ID stored in the SDM memory. |
| • | When 2 LF SIS resets attempted without the correct identification detected |
Action Taken When the DTC Sets
The SDM commands ON the AIR BAG warning lamp via Class 2 serial data.
Conditions for Clearing the DTC
| • | The LF SIS ID matches LF SIS ID stored in SDM memory. |
| • | You can issue a CLEAR CODES command. |
| • | A history DTC will clear once 255 malfunction free ignition cycles have occurred. |
Diagnostic Aids
Ensure that the proper LF side SIS is installed into the vehicle.
Test Description
The following numbers refer to the step numbers in the diagnostic table:
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Did you perform the A Diagnostic System Check? | -- | Go to Step 2 | |
Does the scan tool indicate that this DTC is current? | -- | Go to Step 3 | -- | |
3 | Replace the inflatable restraint side impact sensor (SIS). Refer to Inflatable Restraint Side Impact Sensor Replacement . Did you complete the replacement? | -- | Go to Step 4 | -- |
4 |
Did you complete the action? | -- | -- |
