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. 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.
• | Ignition 1 voltage is within the normal operating voltage range. |
• | Driver frontal deployment loop is not open. |
• | Driver frontal deployment loop is not shorted to voltage. |
• | Driver frontal deployment loop is not shorted to ground. |
• | Driver frontal deployment loop resistance is less than 1.3 ohms for 300 milliseconds. |
The driver frontal deployment loop consists of the following components:
• | Inflatable restraint steering wheel module. |
• | Inflatable restraint steering wheel module coil. |
• | Harness wiring of CKT 347. |
• | Harness wiring of CKT 348. |
• | Connector terminal contact. |
This malfunction is detected during the deployment loop resistance measurement test.
• | The SDM sets a DTC B0022. |
• | The SDM commands ON the AIR BAG warning lamp via Class 2 serial data. |
• | Current DTC |
The resistance of the driver frontal deployment loop is at least 1.3 ohms or more for 300 milliseconds. |
• | History DTC |
- | You issue a scan tool CLEAR CODES command. |
- | Once 250 malfunction free ignition cycles have occurred. |
The following can cause an intermittent condition:
• | A short between CKT 347 and CKT 348. |
• | A malfunctioning shorting bar on the inflatable restraint steering wheel module 2-way connector. |
• | A malfunctioning shorting bar on the inflatable restraint steering wheel module side of inline connector C218. |
The number(s) below refer to the step number(s) on the diagnostic table.
This step checks the inline connector C218.
This step determines if the inflatable restraint steering wheel module coil or the inflatable restraint steering wheel module is defective.
This step determines if there is a short between CKT 347 and CKT 348 or if there is a malfunctioning SDM.
Step | Action | Value(s) | Yes | No |
---|---|---|---|---|
1 | Was the SIR Diagnostic System Check performed? | -- | ||
Is the wiring harness connector OK? | -- | |||
3 | Replace the wiring harness side of inline connector C218. Refer to Wiring Repair . Is the repair complete? | -- | -- | |
4 |
Is DTC B0022 current? | -- | ||
5 |
Is DTC B0022 current? | -- | ||
Is DTC B0022 current? | -- | |||
7 |
Is the repair complete? | -- | -- | |
8 |
Is the repair complete? | -- | -- | |
Is the measured resistance less than the specified value? | OL | |||
10 |
Is the repair complete? | -- | -- | |
11 | Replace the SDM. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement . Is the repair complete? | -- | -- | |
12 |
Have all current and history SIR DTCs been cleared? | -- | -- |