Circuit Description
When you first turn the ignition switch to the RUN position, the inflatable restraint sensing and diagnostic module (SDM) performs tests to diagnose critical malfunctions within itself. Next the SDM measures IGNITION voltage to make sure it is within its respective normal voltage range. Then the SDM proceeds with the DEPLOYMENT LOOP CONTINUITY test. During the DEPLOYMENT LOOP CONTINUITY test, the SDM measures the voltage difference between Driver Side High and Driver Side Low.
Conditions for Setting the DTC
| • | The driver side air bag deployment loop resistance is more than 500 ohms. |
| • | The malfunction must be present for at least 500 milliseconds during one of the following tests: |
| - | DEPLOYMENT LOOP CONTINUITY |
| - | If the malfunction is detected in this test, the RESISTANCE MEASUREMENT test will not be performed. |
| - | CONTINUOUS MONITORING |
Action Taken When the DTC Sets
| • | The SDM sets a Diagnostic Trouble Code. |
| • | The SDM turns ON the AIR BAG warning lamp. |
Conditions for Clearing the DTC
| • | Current DTC |
| The driver side air bag deployment loop resistance is less than 100 ohms for 500 milliseconds. |
| • | History DTC |
| - | You issue a scan tool CLEAR CODES command. |
| - | Once 250 malfunction free ignition cycles have occurred. |
Diagnostic Aids
The following can cause an intermittent condition:
| • | A poor connection at the inflatable restraint driver seat module harness connector terminals A and B. |
| • | A poor connection at the SDM terminals 10 and 11. |
| • | An open in CKT 2137. |
| • | An open in CKT 2138. |
When measurements are requested in this table, use J 39200 Digital Multimeter with the correct terminal adapter from J 35616 Connector Test Adapter Kit. When a check for proper connection is requested, refer to Intermittents and Poor Connections . When a wire, connector or terminal repair is requested, use J-38125 Terminal Repair Kit and refer to Wiring Repair .
Test Description
The numbers below refer to the step numbers on the diagnostic table:
-
This test determines the deployment loop resistance measured by the inflatable restraint sensing and diagnostic module (SDM).
-
This test checks for proper contact or corrosion of the yellow 2-way connector.
-
This test isolates the malfunction to one side of the inflatable restraint front side impact module (LH) yellow 2-way connector.
-
This test checks for proper contact or corrosion of the SDM connector.
-
This test determines whether the malfunction is in CKT 2138.
-
This test determines whether the malfunction is in CKT 2137.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Was the SIR Diagnostic System Check performed? | -- | ||
Has LH SIDE AIR BAG VDIF. been read and recorded on the repair order? | -- | -- | ||
Are the terminals damaged or corroded? | -- | |||
4 | Replace the inflatable restraint front side impact module (LH) yellow 2-way body harness connector. Refer to Wiring Repair . Are the repairs complete? | -- | -- | |
5 | Check for proper connection at terminals A and B on the inflatable restraint front side impact module (LH) yellow 2-way connector. Are the terminals damaged or corroded? | -- | ||
6 | Check for proper connection at terminals A and B on the inflatable restraint front side impact module (LH) yellow 2-way connector. Are the terminals damaged or corroded? | -- | ||
7 | Replace the inflatable restraint front side impact module (LH). Refer to Driver and Passenger Seat Side Inflatable Restraint Module Replacement ? Is the replacement complete? | -- | -- | |
8 |
Is LH SIDE AIR BAG VDIF more than the specified value? | 480 mV | ||
9 |
Are the repairs complete? | -- | -- | |
Is LH SIDE AIR BAG VDIF more than the specified value? | 480 mV | |||
11 |
Is the replacement complete? | -- | -- | |
Is the harness connector damaged or corroded? | -- | |||
13 | Replace the SDM connector. Refer to Wiring Repair . Are the repairs complete? | -- | -- | |
14 | Check for proper connection at terminals 10 and 11 on the SDM. Are the terminals damaged or corroded? | -- | ||
15 | Check for proper connection at terminals 10 and 11 on the SDM. Are the terminals damaged or corroded? | -- | ||
16 | Replace the inflatable restraint Sensing and Diagnostic Module (SDM). Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement . Are the repairs complete? | -- | -- | |
Is the resistance reading within the specified values? | 0-0.5 ohms | |||
18 | Repair the high resistance condition in CKT 2138. Are the repairs complete? | -- | -- | |
Is the resistance reading within the specified values? | 0-0.5 ohms | Go to Integrity Check | ||
20 | Repair the high resistance condition in CKT 2137. Are the repairs complete? | -- | -- | |
21 | Reconnect all the SIR components, make sure all the components are properly mounted. Have all the SIR components been reconnected and properly mounted? | -- | -- | |
22 | Clear all the SIR DTCs. Have all the DTCs been cleared? | -- | -- |
