Circuit Description
When the ignition is turned ON, the inflatable restraint sensing and diagnostic module (SDM) performs tests to diagnose critical malfunctions within itself. Then, the SDM provides input power to the inflatable restraint side impact sensor (SIS) - RF. When the input power is detected, the SIS responds by performing internal diagnostics. After that, 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
Ignition 1 voltage is within the normal operating voltage range.
Conditions for Setting the DTC
The SDM has received a NOK (not OK) message from the SIS.
Action Taken When the DTC Sets
| • | The SDM turns the AIR BAG indicator ON |
| • | The SDM attempts to reset the SIS. |
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. |
Diagnostic Aids
DTC 81 is an indication of an internal malfunction within the SIS.
Test Description
The numbers below refer to the step numbers on the diagnostic table:
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: SIR Schematics | |||
1 | Did you perform A Diagnostic System Check - SIR? | Go to Step 2 | |
With a scan tool, observe the RH SIS MESSAGE STATUS parameter in the SIR data list. Does the scan tool indicate that the RH SIS MESSAGE STATUS parameter is OK? | Go to Step 4 | Go to Step 3 | |
3 |
Did you complete the replacement? | Go to Step 5 | -- |
4 |
Did you complete the replacement? | Go to Step 5 | -- |
5 |
Does the DTC reset? | Go to Step 2 | System OK |
