B1145

Circuit Description
When you first turn the ignition switch to the ON position, the Inflatable Restraint Sensing and Diagnostic Module (SDM) performs tests in order to diagnose critical malfunctions within itself. Upon passing these tests Ignition 1, 23VLR and the deployment loop voltages are measured in order to ensure that they are within their respective normal voltage ranges. The SDM monitors the voltages at Driver Pretensioner Low terminal 23 and Passenger Pretensioner Low terminal 11 in order to detect shorts to voltage in the pretensioner deployment circuits.

Conditions for Setting the DTC
The voltage at Driver Pretensioner Low terminal 23 or, Passenger Pretensioner Low terminal 11, is more than 4.0 volts for 500 milliseconds. The following tests check for this DTC. These tests occur when Ignition 1 is within the normal operating voltage range.
^ Power-On-When the malfunction is detected in this test, the Resistance Measurement test will not be performed.
^ Continuous Monitoring

Action Taken When the DTC Sets
^ The SDM sets a Diagnostic Trouble Code (DTC).
^ The SDM commands the instrument cluster (IPC) to turn ON the AIR BAG warning lamp.

Conditions for Clearing the MIL/DTC
^ The voltage measured at Driver Pretensioner Low and Passenger Pretensioner Low is below 4.0 volts for 500 milliseconds.
^ The ignition switch is turned OFF.

Diagnostic Aids
A short-to-voltage in the passenger pretensioner circuit or the driver pretensioner circuit can cause an intermittent condition. Moving wires while monitoring Driver Pretensioner Senselo and Passenger Pretensioner Senselo may help to locate the fault. Inspect CkT2116, CKT2117, CKT2118, and circuit 2119 carefully for cutting or chafing. The diagnostic table directs the technician to note the entry value of Driver Pretensioner Senselo and Passenger Pretensioner Senselo. Noting the value of Driver Pretensioner Senselo and Passenger Pretensioner Senselo during diagnosis can be helpful in determining if an intermittent condition exists.

When measurements are requested in this table, use J 39200 Digital Multimeter with the correct terminal adapter from J 35616-A Connector Test Adapter Kit. When a check for proper connection is requested, refer to Diagrams. When a wire, connector or terminal repair is requested, use J 38125-B Terminal Repair Kit and refer to Wiring Repair.

Test Description
The numbers below refer to the step numbers on the diagnostic table:
2. This test determines the driver pretensioner voltage measured by the Inflatable Restraint Sensing and Diagnostic Module (SDM) and if the malfunction is currently occurring.
3. This test isolates the malfunction to one side of the driver side air bag/pretensioner yellow 6-way connector.
4. This test isolates the malfunction to the jumper harness or the pretensioner.
7. This test determines whether the malfunction is in circuit 2118.
9. This test determines whether the malfunction is in circuit 2119.
11. This test isolates the malfunction to one side of the passenger side air bag/pretensioner yellow 6-way connector.
12. This test isolates the malfunction to the jumper harness or the pretensioner.
15. This test determines whether the malfunction is in circuit 2117.
17. This test determines whether the malfunction is in circuit 2116.

Notice: When DTC B1125 or DTC B1145 has been set it is necessary to replace the Inflatable Restraint Sensing and Diagnostic Module (SDM). Setting DTC B1125 or DTC B1145 will also cause DTC B1171 to set. When a scan tool clear codes command is issued and the malfunction is no longer present, DTC B1171 will remain current. Make sure that the short to voltage condition is repaired prior to installing a replacement SDM to avoid damaging the SDM.