Circuit Description
When you first turn ON the ignition, the inflatable restraint sensing and diagnostic module (SDM) performs tests to diagnose critical malfunctions within itself. Then the SDM performs the following continuous diagnostic tests on the deployment loops:
| • | Deployment loop voltage out of range test |
| • | Deployment loop resistance measurement test |
If the voltage out of range test detects a short to voltage condition, the resistance measurement test for that deployment loop will not be performed.
Conditions for Running the DTC
Deployment loop voltage out of range test:
| • | Ignition voltage is within the normal operating voltage range. |
| • | Driver frontal deployment loop is not shorted to voltage. |
| • | Driver frontal high terminal A6 is less than 2 volts. |
Deployment loop resistance measurement test:
| • | Ignition voltage is within the normal operating voltage range. |
| • | Driver frontal deployment loop is not shorted to voltage. |
| • | Driver frontal deployment loop is not shorted to ground. |
Conditions for Setting the DTC
Deployment loop voltage out of range test - Driver frontal deployment loop resistance is at least 6 ohms for 300 milliseconds.
Deployment loop resistance measurement test - Driver frontal deployment loop resistance is more than 4.8 ohms for 300 milliseconds.
Action Taken When the DTC Sets
The SDM commands ON the AIR BAG warning lamp 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 can cause an intermittent condition:
| • | The inflatable restraint steering wheel module 2-way connector. |
| • | The inflatable restraint steering wheel module coil 2-way harness connector terminal A and terminal B. |
| • | The SDM wiring harness connector terminal A6 and terminal A7. |
| • | The wire to terminal connections in the driver frontal high circuit. |
| • | The wire to terminal connections in the driver frontal low circuit. |
| • | Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. |
Test Description
The number(s) below refer to the step number(s) on the diagnostic table.
-
This step checks the inflatable restraint steering wheel module coil yellow 2-way connector.
-
This step determines if the inflatable restraint steering wheel module coil or the inflatable restraint steering wheel module is defective.
-
This step checks to see if the SDM wiring harness connector is OK.
-
This step checks to see if there is an open or a high resistance in the driver frontal high circuit.
-
This step determines if there is an open or a high resistance in the driver frontal low circuit or if there is a malfunctioning SDM.
Step | Action | Value(s) | Yes | No | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
1 | Did you perform the SIR Diagnostic System Check? | -- | Go to Step 2 | |||||||
Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. Does either the component or harness side of the inflatable restraint steering wheel module coil yellow 2-way connector exhibit signs of corrosion, terminal damage, or poor connections? | -- | Go to Step 3 | Go to Step 4 | |||||||
3 |
Did you complete the repair? | -- | Go to Step 16 | -- | ||||||
4 |
Does the scan tool indicate that this DTC is current? | -- | Go to Step 5 | Go to Diagnostic Aids | ||||||
5 |
Does the scan tool indicate that this DTC is current? | -- | Go to Step 9 | Go to Step 6 | ||||||
Does the scan tool indicate that this DTC is current? | -- | Go to Step 8 | Go to Step 7 | |||||||
7 |
Did you complete the replacement? | -- | Go to Step 16 | -- | ||||||
8 |
Did you complete the replacement? | -- | Go to Step 16 | -- | ||||||
Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. Does the SDM wiring harness connector exhibit any signs of corrosion, terminal damage, or poor connections? | -- | Go to Step 10 | Go to Step 11 | |||||||
10 | Replace the SDM wiring harness connector. Refer to Connector Repairs in Wiring Systems. Did you complete the repair? | -- | Go to Step 16 | -- | ||||||
Does the resistance measure less than the specified value? | 0.5 ohms | Go to Step 13 | Go to Step 12 | |||||||
12 | Locate and repair the open or the high resistance in the driver frontal high circuit. Refer to Circuit Testing and Wiring Repairs in Wiring systems. Did you complete the repair? | -- | Go to Step 16 | -- | ||||||
Use the DMM to measure the resistance of the driver frontal low circuit. Does the resistance measure less than the specified value? | 0.5 ohms | Go to Step 15 | Go to Step 14 | |||||||
14 | Locate and repair the open or the high resistance in the driver frontal low circuit. Refer to Circuit Testing and Wiring Repairs in Wiring systems. Did you complete the repair? | -- | Go to Step 16 | -- | ||||||
15 | Replace the SDM. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement . Did you complete the replacement? | -- | Go to Step 16 | -- | ||||||
16 |
Did you complete the action? | -- | -- |
