Circuit Description
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. Upon passing theses test the following items are measured to verify that they are within their respective normal voltage ranges:
| • | IGNITION 1 voltage |
| • | 23 VLR |
| • | Deployment loop voltages |
The SDM monitors the voltages at DRIVER SIDE LOW terminal 3 and PASSENGER SIDE LOW terminal 4 to detect shorts to B+ in the inflator module circuits.
Conditions for Setting the DTC
| • | The voltage at DRIVER SIDE LOW terminal 3 is less than 4.8 volts. |
| • | The voltage at PASSENGER SIDE LOW terminal 4 is more than 4.8 volts for 500 milliseconds. |
The CONTINUOUS MONITORING test inspects for this DTC. This test occurs when IGNITION 1 voltage is within the normal operating voltage range.
Action Taken When the DTC Sets
The SDM turns ON the AIR BAG warning lamp.
Conditions for Clearing the DTC
| • | Current DTC-The voltage at PASSENGER SIDE LOW terminal 4 is less than 4.8 volts for 500 milliseconds. |
| • | History DTC |
| - | You issue a scan tool CLEAR CODES command. |
| - | After 250 malfunction free ignition cycles have occurred. |
Diagnostic Aids
A short to B+ in the inflatable restraint IP module circuit may cause an intermittent condition. Inspect CKT 1403 and CKT 1404 carefully for cutting or chafing. Wiring pigtail damage requires replacement of the inflatable restraint IP module. The diagnostic table directs the technician to note the entry value of PASSENGER SENSELO. Comparing the value of PASSENGER SENSELO may be helpful in determining if an intermittent condition exists.
When measurements are requested in this table, use the J 39200 Digital Multimeter with the correct terminal adapter from the J 35616 Connector Test Adapter Kit. When an inspection for proper connection is requested, refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems. When a wire, connector or terminal repair is requested, use the J-38125 Terminal Repair Kit. Refer to Wiring Repairs in Wiring Systems.
Test Description
The numbers below refer to the step numbers on the diagnostic table:
-
This test determines the passenger side low voltage which is measured by the inflatable restraint sensing and diagnostic module (SDM).
-
This test isolates the malfunction to one side of the inflatable restraint IP module yellow 2-way connector.
-
This test determines whether the malfunction is due to the inflatable restraint IP module or the IP module jumper.
-
This test determines whether the malfunction is in CKT 1403.
-
This test determines whether the malfunction is in CKT 1404.
Step | Action | Value(s) | Yes | No |
|---|---|---|---|---|
1 | Was the SIR Diagnostic System Check performed? | -- | Go to Step 2 | |
Has the PASSENGER SENSELO been read and recorded on the repair order? | -- | Go to Step 3 | -- | |
Is PASSENGER SENSELO more than the specified value? | 4.8 V | Go to Step 7 | Go to Step 4 | |
Is PASSENGER SENSELO more than the specified value? | 4.8 V | Go to Step 5 | Go to Step 6 | |
5 |
Is the repair complete? | -- | Go to Step 11 | -- |
6 |
Is the repair complete? | -- | Go to Step 11 | -- |
Is the measured voltage less than the specified value? | 1.0 V | Go to Step 9 | Go to Step 8 | |
8 |
Is the repair complete? | -- | Go to Step 11 | -- |
Measure the voltage on the SDM harness connector from terminal 4 to terminal 6 to ground. Is the measured voltage less than the specified value? | 1.0 V | Go to Step 10 | ||
10 |
Is the repair complete? | -- | Go to Step 11 | -- |
11 |
Have all SIR components been reconnected and properly mounted? | -- | Go to Step 12 | -- |
12 | Clear all SIR DTCs. Have all SIR DTCs been cleared? | -- | -- |
