Circuit Description
When you turn the ignition switch to the ON position, the inflatable restraint Sensing and Diagnostic Module (SDM) performs tests in order to diagnose critical malfunctions. Upon passing these tests, the system measures IGNITION 1 voltage, the 23-volt loop reserve, and the deployment loop voltages in order to verify the normal ranges. The SDM monitors the voltages at the driver-side low terminal 10 and at the passenger-side low terminal 3 in order to detect shorts to ground in the inflator module circuits.
Conditions for Setting the DTC
| • | The driver deployment loop is not open. |
| • | The passenger deployment loop is not open. |
| • | The passenger deployment loop is not shorted to voltage. |
| • | The voltage at Passenger Side Low terminal 3 is more than 1.5 volts. |
| • | The voltage at driver-side low terminal 10 is less than 1.5 volts for 500 milliseconds. |
The following tests check for the DTC. These tests occur if IGNITION 1 is within the normal operating voltage range:
| • | If the malfunction is detected in the Power-On Test, the Resistance 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 if the voltage at driver-side low terminal 10 is more than 1.5 volts for 500 milliseconds. |
| • | Clear the History DTC under the following conditions: |
| - | Use a scan tool in order to clear the DTCs. |
| - | If 250 malfunction-free ignition cycles have occurred. |
Diagnostic Aids
A short to ground in the circuit of the inflatable restraint steering module can cause an intermittent condition. Move the wires, and monitor the DRIVER SENSELO in order to find the fault. Carefully inspect the GRN/RED wire and the GRN wire for broken wires or for chafed wires. The diagnostic table directs the technician to note the entry value of the DRIVER SENSELO in order to determine if an intermittent condition exists.
If this table requests measurements, use the J 39200 Digital Multimeter with the correct terminal adapter from the J 35616 Connector Test Adapter Kit. If a check for a correct connection is requested, refer to Testing for Intermittent Conditions and Poor Connections . If a wire repair, a connector repair, or a terminal repair is requested, use the J-38125 Terminal Repair Kit, and refer to Wiring Repair .
DTC Table Test Description
Numbers below refer to step numbers on the diagnostic table.
-
This step determines the Driver Side Low voltage measured by the inflatable restraint Sensing and Diagnostic Module (SDM).
-
This step isolates the malfunction to one side of the yellow 2-way connector on the inflatable restraint steering wheel module coil. This connector is located near the base of the steering column.
-
This step determines whether the malfunction is in the inflatable restraint steering wheel module coil or in the inflatable restraint steering wheel module.
-
This step determines whether the malfunction is in the GREN/RED wire.
-
This step determines whether the malfunction is in the GRN wire.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Was the SIR Diagnostic System Check performed? | -- | ||
Is the DRIVER SENSELO less than the specified value? | 3.3 V | Refer to Diagnostic Aids | ||
Is DRIVER SENSELO less than the specified value? | 3.3 V | |||
Is DRIVER SENSELO less than the specified value? | 3.3 V | |||
5 |
Have you replaced the inflatable restraint steering wheel module? | -- | -- | |
6 |
Have you replaced the inflatable restraint steering wheel module coil? | -- | -- | |
Is the resistance reading less than the specified value? | OL (Infinite) | |||
8 | Repair a short to ground condition in the GRN/RED wire. Is the circuit repair complete? | -- | -- | |
Measure the resistance on the SDM harness connector from terminal 10 to terminal 6 (ground). Is the resistance reading less than the specified value? | OL (Infinite) | |||
10 | Repair a short to ground condition in the GRN wire. Is the circuit repair complete? | -- | -- | |
11 | Reconnect and mount all the SIR system components. Have you reconnected and properly mounted all of the SIR components? | -- | -- | |
12 | Clear the SIR diagnostic trouble codes. Have you cleared the SIR diagnostic trouble codes? | -- | -- |
