The inflatable restraint electronic frontal sensor (EFS), also known as inflatable restraint front end discriminating sensor, loop is a 2 wire circuit. When the ignition is turned ON, the inflatable restraint sensing and diagnostic module (SDM) performs tests to diagnose critical malfunctions within itself. The SDM provides input power to the EFS. When input power is first detected, the EFS responds by performing internal diagnostics. Next the EFS 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 EFS is powered up. The EFS will continually communicate a status message to the SDM. The SDM can reset the EFS by removing and applying power to it.
The SDM monitors the EFS loop with power on.
• | EFS will send an ID message to the SDM. |
• | EFS will continuously send OK or NOK message to SDM. |
• | Ignition 1 Voltage is within normal operating voltage range |
• | The SDM has received an ID message from the EFS which does not match the ID stored in the SDM memory. |
• | When 2 EFS resets attempted without the correct identification detected. |
The SDM commands ON the AIR BAG warning indicator via Class 2 serial data.
• | 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. |
Check to ensure that the proper EFS is installed into vehicle.
The following numbers refer to the step numbers in the diagnostic table:
Step | Action | Yes | No |
---|---|---|---|
Schematic Reference: SIR Schematics | |||
1 | Did you perform A Diagnostic System Check - SIR? | Go to Step 2 | |
Does the scan tool indicate that this DTC B0102 is current? | Go to Step 3 | -- | |
3 | Replace the inflatable restraint electronic frontal sensor (EFS), also known as inflatable restraint front end discriminating sensor. Refer to Inflatable Restraint Front End Discriminating Sensor Replacement . Did you complete the replacement? | Go to Step 4 | -- |
4 |
Does the DTC reset? | Go to Step 2 | System OK |