Circuit Description
The inflatable restraint side impact module-LF deployment loop consists of the inflatable restraint side impact module-LF, the inflatable restraint side impact module wiring harness, and the side impact module-LF high and low circuits. A shorting bar used within the side impact module-LF connector shorts together the side impact module-LF high and low circuits when the connector is disconnected. This helps to prevent unwanted deployment of the inflator module during servicing. During a side or frontal crash of sufficient force the inflatable restraint Sensing and Diagnostic Module (SDM) allows current to flow through the deployment loop in order to deploy the side impact module-LF. When the ignition is turned ON, the SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. If a malfunction is detected, a Diagnostic Trouble Code (DTC) will be stored in memory.
Conditions for Running the DTC
Ignition 1 voltage is within the normal operating voltage range.
Conditions for Setting the DTC
| • | DTC B0040 will set when the side impact module-LF deployment loop resistance is less than 1.3 ohms for 500 milliseconds. |
| • | DTC B0041 will set when one of the following conditions occurs: |
| - | Side impact module-LF high circuit is less than 2.4 volts and the side impact module-LF deployment loop is more than 6 ohms for 500 milliseconds. |
| - | Side impact module-LF deployment loop resistance is more than 4.8 ohms for 500 milliseconds. |
| • | DTC B0045 will set when one of the following conditions occur: |
| • | Side impact module-LF high circuit is more than 6 volts for 500 milliseconds. |
| • | Side impact module-LF high circuit is less than 2.4 volts and side impact module-LF deployment loop resistance is less than 6 ohms for 500 milliseconds. |
Action Taken When the DTC Sets
The SDM commands the AIR BAG indicator ON via Class 2 serial data.
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
The following are possible causes of the malfunction:
| • | A short between the side impact module-LF high and low circuits |
| • | An open or a high resistance in the side impact module-LF high or low circuits |
| • | A short to ground or a short to voltage in the side impact module-LF high or low circuits |
| • | The side impact module-LF connector |
| • | The SDM connector |
| • | A malfunctioning side impact module-LF |
| • | A malfunctioning SDM |
Thoroughly inspect the wiring and the connectors. An incomplete inspection of the wiring and the connectors may result in a misdiagnosis, causing a part replacement with the reappearance of the malfunction. If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.
Test Description
The number below refer to the step number on the diagnostic table.
Step | Action | Yes | No |
|---|---|---|---|
Schematic Reference: SIR Schematics | |||
1 | Did you perform the Diagnostic System Check - SIR? | Go to Step 2 | |
2 |
Does the side impact module-LF connector exhibit any signs of damage or corrosion? | Go to Step 3 | Go to Step 4 |
3 |
Did you complete the repair? | Go to Step 9 | -- |
4 |
Does the scan tool indicate that DTC B0040, B0041, or B0045 are current? | Go to Step 6 | Go to Step 5 |
5 |
Did you complete the replacement? | Go to Step 9 | -- |
6 |
Did you find and correct the condition? | Go to Step 9 | Go to Step 7 |
Did you find and correct the condition? | Go to Step 9 | Go to Step 8 | |
8 |
Did you complete the replacement? | Go to Step 9 | -- |
9 |
Does the DTC reset? | Go to Step 2 | System OK |
