B1036

Circuit Description
When you first turn the ignition switch to the RUN position, the Inflatable Restraint Sensing and Diagnostic Module (SDM) performs tests in order to diagnose critical malfunctions within the SDM. Upon passing these tests the following circuits are measured in order to ensure they are within their respective normal voltage ranges:
^ IGNITION 1
^ 23 VLR
^ Deployment loop voltages
Then, the SDM proceeds to CONTINUOUS MONITORING. The SDM contains a resistor network connected to 5 volts, ground, and to the SDM Front-End Sensor signal terminal 9. The SDM monitors two Front End Discriminating Sensors that are wired in parallel. The 1.0 K resistor in the right Inflatable Restraint Front End Discriminating Sensor parallel to the normally open switches in both sensors and provides a parallel path to ground. This causes a specified percentage of voltage to appear at the SDM front-end sensor signal input. The SDM monitors this voltage to detect shorts to power or an open Discriminating Sensor.

Conditions for Setting the DTC
^ The SDM is configured for an Inflatable Restraint Front End Discriminating Sensor
^ The voltage at Front-End Sensor signal terminal 9 is more than 5.0 volts for 500 milliseconds.
The CONTINUOUS MONITORING test inspects for this DTC. This test occurs when IGNITION 1 is within the normal operating voltage range.

Action Taken When the DTC Sets
^ The SDM sets a diagnostic trouble code.
^ The SDM turns the AIR BAG warning lamp to the ON position.

Conditions for Clearing the DTC
^ Current DTC-The voltage at Front-End Sensor signal terminal 9 is less than 3.2 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 broken or chafed wire in the Inflatable Restraint Front End Discriminating Sensor circuit can cause an intermittent condition. Inspect circuit 1834 and circuit 1851 carefully for culling or chafing.
When measurements are requested in this table, use the J 39200 DMM with the correct terminal adapter from the J 35616-A Connector Test Adapter Kit.

Test Description
The numbers below refer to the step numbers on the diagnostic table:
2. This test inspects for proper contact or corrosion of the yellow 2-way connector.
7. This test inspects for a malfunctioning Discriminating Sensor.
8. This test inspects for an open in circuit 1851.
18. This test inspects for proper contact or corrosion of the Inflatable Restraint Sensing and Diagnostic Module (SDM) connector.
23. This test inspects for an open in circuit 1834.
33. This test isolates the open in circuit 1834 to one side of C109.
36. This test inspects for a short to voltage in circuit 1834.