The inflatable restraint sensing and diagnostic module (SDM) monitors the inflatable restraint front end sensor circuit for front impact detection. The SDM processes the signal provided by the front end sensor to further support deployment of the air bags. The front end sensor is an input only to the SDM and does not directly cause air bag deployment. When the ignition is turned ON, the SDM performs continuous diagnostic tests on the deployment loops to check for proper circuit continuity and for shorts to ground or voltage. If a malfunction is detected, a diagnostic trouble code (DTC) will be stored.
This diagnostic procedure supports the following DTC:
DTC B0036 Auxiliary Discriminating Sensor (ADS) Open, Missing, or Shorted to Battery
CONDITIONS FOR RUNNING THE DTC
Ignition 1 voltage is within the normal operating voltage range.
CONDITIONS FOR SETTING THE DTC
The SDM detects the voltage at the front end sensor signal is greater than 3.65 volts for 300 milliseconds.
ACTION TAKEN WHEN THE DTC SETS
The SDM commands ON the AIR BAG indicator via class 2 serial data.
CONDITIONS FOR CLEARING THE DTC
The condition responsible for setting the DTC no longer exists, and the scan tool clear DTCs function is used.
A history DTC will clear once 255 malfunction free ignition cycles have occurred.
The following are conditions that may cause the malfunction:
A short to voltage in either the front end sensor voltage or ground circuits.
High or low resistance in either the front end sensor voltage or ground circuits.
A broken or chafed wire in either the front end sensor voltage or ground circuits.
Thoroughly inspect the wiring and the connectors. An incomplete inspection of the wiring and connectors may result in misdiagnosis, causing a part replacement with the reappearance of the malfunction. If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections in Diagnostic Aids.
Codes never identify bad parts, just failed systems.
Friday, January 18th, 2013 AT 2:11 AM