Circuit Description
When you first turn the ignition switch to the ON position, the inflatable restraint Sensing and Diagnostic Module (SDM) performs tests to diagnose critical malfunctions within itself. Next the SDM measures IGNITION 1 voltage to make sure it is within its respective normal voltage ranges. 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 the DRIVER SIDE LOW.
Conditions for Setting the DTC
| • | The voltage difference between the DRIVER SIDE HIGH terminal 9 and DRIVER SIDE LOW terminal 10 is more than or equal to 400 millivolts. |
| • | The malfunction must be present for at least 500 milliseconds during one of the following tests: |
| - | If the malfunction is detected in the DEPLOYMENT CONTINUITY test, the RESISTANT MEASUREMENT test will not be performed. |
| - | The CONTINUOUS MONITORING test. |
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
| • | Clear the Current DTC when the voltage difference between the DRIVER SIDE HIGH terminal 9 and DRIVER SIDE LOW terminal 10 is less than 400 millivolts for 500 milliseconds. |
| • | Clear the HISTORY DTC under the following conditions: |
| - | You issue a scan tool CLEAR CODES command. |
| - | 250 malfunction free ignition cycles have occurred. |
Diagnostic Aids
The following can cause an intermittent condition:
| • | A poor connection at the inflatable restraint steering wheel module steering column connector terminal 1 and terminal 2. |
| • | A poor connection at the upper inflatable restraint steering wheel module coil connector terminal 1 and terminal 2. |
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 in this section.
Test Description
Numbers below refer to step numbers on the diagnostic table.
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This step determines the deployment loop voltage difference measured by the SIR Sensing and Diagnostic Module (SDM).
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This step checks for proper contact or corrosion of the yellow 2-way connector.
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This step isolates the malfunction to one side of the yellow 2-way connector on the inflatable restraint steering wheel module. This connector is located near the base of the steering column.
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This step determines whether the malfunction is in the inflatable restraint steering wheel module coil or in the inflatable restraint steering wheel module.
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This step checks for proper contact or corrosion of the SDM connector.
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This step checks for proper contact or corrosion of the SDM connector.
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This test determines whether the malfunction is in the GRN/RED wire.
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This test determines whether the malfunction is in the GRN wire.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Was the SIR Diagnostic System Check performed? | -- | ||
Have you read the DRIVER VDIF and recorded the value on the repair order? | -- | -- | ||
Are the terminals damaged or corroded? | -- | |||
4 | Replace the yellow 2-way harness connector at the base of the steering column. Refer to SIR Connector (Plastic Body and Terminal Metal Pin) Repair portion of Wiring Repair . Have you replaced the yellow 2-way harness connector? | -- | -- | |
5 | Check for a proper connection at the terminal D3 and terminal D4 on the inflatable restraint steering wheel module coil side of the 2-way connector. Are the terminals damaged or corroded? | -- | ||
6 | Check for a proper connection at the terminal D3 and terminal D4 on the inflatable restraint steering wheel module coil side of the 2-way connector. Are the terminals damaged or corroded? | -- | ||
7 | Replace the inflatable restraint steering wheel module coil. Refer to Inflatable Restraint Steering Wheel Module Coil Replacement . Have you replaced the inflatable restraint steering wheel module coil? | -- | -- | |
8 |
Is DRIVER VDIF more than the specified value? | 400 mV | ||
9 |
Have you replaced the yellow 2-way harness connector? | -- | ||
Is DRIVER VDIF more than the specified value? | 400 mV | |||
Is DRIVER VDIF more than the specified value? | 400 mV | |||
Have you replaced the inflatable restraint steering wheel module? | -- | -- | ||
13 |
Have you replaced the inflatable restraint steering wheel module? | -- | -- | |
Is the SDM harness connector damaged or corroded? | -- | |||
15 | Replace the SDM harness connector. Refer to SIR Connector (Plastic Body and Terminal Metal Pin) Repair portion of Wiring Repair . Have you replaced the SDM harness connector? | -- | -- | |
16 | Check for a proper connection at terminal 9 and 10 on the SDM. Are the SDM terminals damaged or corroded? | -- | ||
17 | Check for a proper connection at terminal 9 and terminal 10 on the SDM. Are the SDM terminals damaged or corroded? | -- | ||
18 | Replace the SDM. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement . Have you replaced the SDM? | -- | -- | |
Is the resistance reading within the specified values? | 0-0.5ohms | |||
20 | Repair the high resistance in the GRN/RED wire. Have you repaired the circuit? | -- | -- | |
Is the resistance reading within the specified values? | 0-0.5ohms | |||
22 | Repair the high resistance in the GRN wire. Have you repaired the circuit? | -- | -- | |
23 | Reconnect and mount all of the SIR system components. Have you reconnected and properly mounted all the SIR components? | -- | -- | |
24 | Clear the SIR diagnostic trouble codes. Have you cleared the SIR Diagnostic trouble codes? | -- | -- |
