GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2001 🢒 LeSabre 🢒 Restraints 🢒 SIR 🢒 DTC B0101

Circuit Description

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.

Conditions for Running the DTC

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.

Conditions for Running the DTC

The SDM monitors the EFS loop with power on.

Conditions for Setting the DTC
    • Ignition 1 Voltage is within the normal operating voltage range.
    • The SDM has received a NOK (not OK) message from the EFS.

Action Taken When the DTC Sets

The SDM commands ON the AIR BAG warning indicator via Class 2 serial data.

Conditions for Clearing the DTC
    • Replace the EFS.
    • 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

Check to ensure that the proper EFS is installed into vehicle.

Test Description

The following numbers refers to the step numbers in the diagnostic table:

  1. This test checks the communication status of the EFS.

Step

Action

Yes

No

Schematic Reference: SIR Schematics

1

Did you perform A Diagnostic System Check - SIR?

Go to Step 2

Go to Diagnostic System Check - SIR

2

  1. Turn OFF the ignition.
  2. Install scan tool.
  3. Turn ON the ignition, with the engine OFF.
  4. Use the scan tool to request SIR DTCs display.

Does the scan tool indicate that this DTC B0101 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
  1. Use the scan tool in order to Clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the text.

Does the DTC reset?

Go to Step 2

System OK