Circuit Description
During normal, non-deployment operation of the Supplemental Restraint System (SRS), the supplemental restraint Diagnostic Energy Reserve Module (DERM) monitors the voltage supplied through the supplemental restraint arming sensor to the high side of the driver deployment loop at the Driver Source Sense terminal A5. This measured voltage will have a value approximately equal to the Driver 36 VLR. When the voltage at the Driver Side Low terminal B8 measures in its normal operating range, indicating driver deployment loop integrity has been maintained and at the same time, the voltage the Driver Source Sense terminal A5 measures at a specified amount below Driver 36 VLR for 500 milliseconds, DTC B1043 will set.
Conditions for Setting the DTC
The DTC sets when the DERM measures simultaneously:
| • | The Driver Side Low terminal B8 voltage within a specified percentage of the Driver 36 VLR. |
| • | The Driver Source Sense terminal A5 voltage at a specified amount below the Driver 36 VLR for 500 milliseconds during Continuous Monitoring tests. |
Action Taken When the DTC Sets
The DERM turns on the AIR BAG warning lamp and sets a diagnostic trouble code.
Conditions for Clearing the DTC
The DTC clears when the DERM measures simultaneously:
- The Driver Side Low terminal B8 voltage within a specified percentage of the Driver 36 VLR.
- The Driver Source Sense terminal A5 voltage at a specified amount below the Driver 36 VLR for 500 milliseconds during Continuous Monitoring tests.
Diagnostic Aids
One of the following situations may cause an intermittent condition:
| • | A poor connection to the DERM at terminal A5 |
| • | A poor connection to the supplemental restraint arming sensor or supplemental restraint arming sensor jumper harness electrical connector at terminal C |
| • | An open or short to ground in the CKT 1400 |
| • | A open supplemental restraint arming sensor |
Test Description
Refer to step numbers on the diagnostic table.
-
Start at the SRS Diagnostic System Check for all diagnosis.
-
This test checks for an open in the Driver Source Sense circuit.
-
This test locates the open in the Driver Source Sense circuit.
-
This test checks for a short from the Driver Source Sense circuit-to-ground.
-
This test locates the short from the Driver Source Sense circuit-to-ground.
-
This test determines whether the malfunction is due to increased resistance across the Driver Source Sense resistor in the Arming Sensor.
When measurements are requested in this table, use J 39200 Digital Multimeter with correct terminal adapter from J 35616 Connector Test Adapter Kit. When a check for proper connection is requested, refer to Intermittents and Poor Connections in Section 8A4. When a wire, connector or terminal repair is requested, use J-38125 Terminal Repair Kit and refer to Wiring Repair.
Step | Action | Value | Yes | No |
|---|---|---|---|---|
Was the SRS Diagnostic System Check performed? | -- | |||
2 |
Is the DERM electrical harness connector damaged or corroded? | -- | ||
3 | Repair the DERM electrical harness connector. Has the connector been repaired? | -- | -- | |
4 | Check for proper connection to the DERM at terminal A5. Are the DERM terminals damaged or corroded? | -- | ||
5 | Check for proper connection to the DERM at terminal A5. Are the DERM terminals damaged or corroded? | -- | ||
6 | Replace the DERM. Refer to Supl Rst Diagnostic Energy Reserve Module . Has the DERM been replaced? | -- | -- | |
7 |
Is the supplemental restraint arming sensor electrical harness connector damaged or corroded? | -- | ||
8 | Replace the supplemental restraint arming sensor electrical harness connector. Has the connector been replaced? | -- | -- | |
9 | Check for proper connection to the supplemental restraint arming sensor at terminal C. Is the terminal damaged or corroded? | -- | ||
10 | Check for proper connection to the supplemental restraint arming sensor at terminal C. Is the terminal damaged or corroded? | -- | ||
11 | Replace the supplemental restraint arming sensor. Refer to Supl Rst Arming Sensor . Has the supplemental restraint arming sensor been replaced? | -- | -- | |
Measure the resistance from the DERM electrical harness connector terminal A5 to the supplemental restraint arming sensor electrical harness connector terminal C. Is the resistance less than the value specified? | 5 ohms | |||
13 |
Is the connector terminal C damaged or corroded? | -- | ||
14 | Repair the supplemental restraint arming sensor jumper harness electrical connector C110. Has the connector been repaired? | -- | -- | |
Measure the resistance of circuit 1400 from the DERM electrical harness connector terminal A5 to the supplemental restraint arming sensor jumper harness electrical connector terminal C. Is the resistance less than the specified value? | 5 ohms | |||
16 | Repair the open in circuit 1400 in the supplemental restraint arming sensor jumper harness. Has the open circuit been repaired? | -- | -- | |
17 | Repair the open in circuit 1400 in the SRS wiring harness. Has the open circuit been repaired? | -- | ||
Measure the resistance on the DERM electrical harness connector terminal A5 to terminal A1 (ground). Does J 39200 display OL (infinite)? | -- | |||
Does J 39200 display OL (infinite)? | -- | |||
20 | Repair the short-to-ground in circuit 1400 in the supplemental restraint arming sensor jumper harness. Has the short circuit been repaired? | -- | -- | |
21 | Repair the short-to-ground in circuit 1400 in the SRS wiring harness. Has the short circuit been repaired? | -- | -- | |
Measure the resistance of the supplemental restraint arming sensor from terminal C to terminal D. Is the resistance more than the value specified? | 7.67 kohms | Go to Integrity Check | ||
23 |
Have all the SRS components been reconnected and properly mounted? | -- | -- | |
24 | Clear the SRS Diagnostic Trouble Codes. Have the SRS Diagnostic Trouble Codes been cleared? | -- | -- |
