Circuit Description
When the ignition is first turned ON, the inflatable restraint sensing and diagnostic module (SDM) compares the restraints ID stored in the SDM to the restraints ID stored in the body control module (BCM). The restraints ID being compared contains the last four digits of the SDM part number. The SDM then compares the vehicle identification number (VIN) stored in the SDM to the VIN stored in the BCM. For more detailed information concerning the Class 2 data lines, refer to Data Link Communications Description and Operation in Data Link Communications.
Conditions for Setting the DTC
| • | Ignition 1 voltage is within the normal operating voltage range. |
| • | The restraints ID stored in the SDM does not match the restraints ID stored in the BCM, or the VIN information stored in the SDM does not match the VIN information stored in the BCM. |
This test is only run once during power up initialization.
Action Taken When the DTC Sets
| • | The SDM commands ON the AIR BAG indicator via Class 2 serial data. |
| • | The SDM disables all AIR BAG deployments. |
Conditions for Clearing the DTC
| • | You issue a scan tool CLEAR DTCs command. |
| • | A history DTC will clear once 255 malfunction free ignition cycles have occurred. |
When the SDM detects that no DTCs are present, the SDM commands the AIR BAG indicator OFF.
Diagnostic Aids
DTC B1001 is an indication that the restraint IDs stored in both the BCM and SDM do not match or that the VINs stored in both the BCM and SDM do not match. If either the BCM or powertrain control module (PCM) were replaced, the replacement modules need to be reprogrammed for proper operation.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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This step checks to see if the correct VIN is programmed in the PCM.
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This step checks to see if the BCM has been replaced.
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This step explains the proper steps to perform after a BCM has been replaced in order for the BCM to operate properly.
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This step checks to see if the correct VIN is programmed in the BCM.
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This step explains how to properly program the VIN into the BCM.
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This step checks to see if the SDM has been replaced.
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This step explains how to properly setup the SDM and BCM.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
Schematic Reference: SIR Schematics Connector End View Reference: SIR Connector End Views | ||||
1 | Did you perform the Diagnostic System Check - SIR? | -- | Go to Step 2 | |
Is the PCM programmed with the correct VIN? | -- | Go to Step 4 | Go to Step 3 | |
3 | Use the scan tool and/or the techline machine to program the correct VIN into the PCM. Did you complete the programming procedure? | -- | Go to Step 11 | -- |
Was the body control module (BCM) replaced? | -- | Go to Step 5 | Go to Step 6 | |
Program the BCM in order for the BCM to learn the restraints ID from the SDM. Refer to Body Control Module (BCM) Programming/RPO Configuration in Body Control System. Did you complete the programming procedures? | -- | Go to Step 10 | -- | |
Use the scan tool to verify that the BCM is programmed with the correct VIN by comparing the VIN that is stored in the BCM to the VIN that is stored in the PCM. Is the BCM programmed with the correct VIN? | -- | Go to Step 8 | Go to Step 7 | |
Program the correct VIN into the BCM. Refer to Body Control Module (BCM) Programming/RPO Configuration in Body Control System. Did you complete the reprogramming procedure? | -- | Go to Step 10 | -- | |
Was the sensing and diagnostic module (SDM) replaced? | -- | Go to Step 10 | Go to Step 9 | |
9 | Replace the inflatable SDM. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement . Did you complete the replacement? | -- | Go to Step 10 | -- |
Perform the Relearn Restraints ID Procedure. Refer to Body Control Module (BCM) Programming/RPO Configuration in Body Control System. Did you complete the setup procedure? | -- | Go to Step 11 | -- | |
11 |
Are all SIR components properly mounted and connected? | -- | -- | |
