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. Next, the SDM measures IGNITION 1 voltage in order to verify the normal voltage range. Then, the SDM proceeds with the Deployment Loop Continuity test. During the Deployment Loop Continuity test, the SDM measures the voltage difference between Passenger Side High and Passenger Side Low.
Conditions for Setting the DTC
| • | The voltage difference between the Passenger Side High terminal 4 and the Passenger Side Low terminal 3 is more than or equal to 400 millivolts. |
| • | The malfunction must be present for at least 500 milliseconds during one of the following tests: |
| - | The Deployment Loop Continuity Test.If the malfunction is detected in this 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 difference between the passenger-side high terminal 4 and the passenger-side low terminal 3 is less than 400 mV for 500 milliseconds. |
| • | Clear the History DTC under the following conditions: |
| - | Use a scan tool in order to clear the DTCs. |
| - | 250 malfunction-free ignition cycles have occurred. |
Diagnostic Aids
The following conditions can cause an intermittent:
| • | A poor connection at terminal 1 and at terminal 2 of the harness connector of the inflatable restraint IP module. |
| • | A poor connection at terminal 4 and at terminal 3 of the SDM. |
| • | An open in the YEL /RED wire. |
| • | An open in the YEL wire. |
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 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 in this section.
Test Description
The numbers below refer to step numbers on the diagnostic table.
-
This determines the difference of the passenger deployment loop voltage that the Sensing and Diagnostic Module (SDM) measures.
-
The test checks for correct contact and/or for corrosion of the yellow connector.
-
This test isolates the malfunction to one side of the yellow connector of the inflatable restraint IP module. This is done by substituting the known good resistance of the load tool and observing if the malfunction is still present.
-
This test checks for correct contact and/or for corrosion of the SDM connector.
-
This test determines if the malfunction is in the YEL/RED wire.
-
This test determines if the malfunction is in the YEL wire.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
1 | Was the SIR Diagnostic System Check performed? | -- | ||
Did you record the PASSENGER VDIF on the repair order? | -- | -- | ||
Are the terminals damaged or corroded? | -- | |||
4 | Replace the harness connector of the inflatable restraint IP module. Refer to SIR Connector (Plastic Body and Terminal Metal Pin) Repair portion of Wiring Repair in this section. Did you replace the harness connector of the inflatable restraint IP module? | -- | -- | |
5 | Check the connection at terminal 1 and at terminal 2 on the connector of the inflatable restraint IP module. Are the terminals damaged or corroded? | -- | ||
6 | Check for the correct connection at terminal B1 and at terminal B2 on the connector of the inflatable restraint IP module. Are the terminals damaged or corroded? | -- | ||
7 | Replace the inflatable restraint IP module. Refer to Inflatable Restraint Instrument Panel Module Replacement . Did you replace the inflatable restraint IP module? | -- | -- | |
8 |
Is the PASSENGER VDIF more than the specified value? | 400 mV | ||
9 |
Did you replace the harness connector of the inflatable restraint IP module? | -- | -- | |
Is the PASSENGER VDIF more than the specified value? | 400 mV | |||
11 |
Did you replace the inflatable restraint IP module? | -- | -- | |
Is the SDM harness connector damaged or corroded? | -- | |||
13 | Replace the SDM harness connector. Refer to SIR Connector (Plastic Body and Terminal Metal Pin) Repair portion of Wiring Repair . Did you replace the SDM harness connector? | -- | -- | |
14 | Check for the correct connection at terminal 4 and at terminal 3 in the SDM. Are the SDM terminals damaged or corroded? | -- | ||
15 | Check for the correct connection at terminal 4 and at terminal 3 in the SDM. Are the SDM terminals damaged or corroded? | -- | ||
16 | Replace the SDM. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement . Did you replace the SDM? | -- | -- | |
Zero the J 39200 . Measure the resistance from the SDM harness connector terminal 4 to harness connector terminal 2 of the inflatable restraint IP module. Is the resistance reading within specified values? | 0-0.5 ohms | |||
18 | Repair the high resistance in the YEL/RED wire. Is the circuit repair complete? | -- | -- | |
Zero the J 39200 . Measure the resistance from the SDM's harness connector terminal 3 to harness connector terminal 1 of the inflatable restraint IP module. Is the resistance reading within specified values? | 0-0.5 ohms | |||
20 | Repair high resistance in the YEL wire. Is the circuit repair complete? | -- | -- | |
21 | Reconnect all the SIR system components. Verify that all the components are correctly mounted. Did you reconnect all the SIR components? Did you correctly mount all the SIR components? | -- | -- | |
22 | Clear the SIR diagnostic trouble codes. Did you clear the SIR diagnostic trouble codes? | -- | -- |
