B1135

Diagnostic Chart:

Wiring Diagram:

CIRCUIT DESCRIPTION
When you first turn ON the ignition, the inflatable restraint sensing and diagnostic module (SDM) performs tests to diagnose critical malfunctions within itself. 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 feed. The 1.0 K Ohms resistor in the inflatable restraint front end discriminating sensor parallel to the normally open switch provides a parallel path to ground. This causes a specified percentage of voltage in order to appear at the SDM front end sensor feed input. The SDM monitors this voltage in order to detect shorts to ground or a closed discriminating sensor.

CONDITIONS FOR RUNNING THE DTC
^ The SDM is configured for an inflatable restraint front end discriminating sensor.
^ Ignition 1 voltage is within the normal operating voltage range.
^ Front end discriminating sensor input circuit is not shorted to ground.

CONDITIONS FOR SETTING THE DTC
The voltage at front end discriminating sensor input terminal is less than or equal to 0.7 volts for 500 milliseconds.

ACTION TAKEN WHEN THE DTC SETS
The SDM commands ON the AIR BAG warning lamp via Class 2 serial data.

CONDITIONS FOR CLEARING THE DTC
^ The voltage at front end sensor input is more than 0.7 volts for 500 milliseconds.
^ You can issue a CLEAR CODES command
^ A history DTC will clear once 250 malfunction free ignition cycles have occurred

DIAGNOSTIC AIDS
The following can cause an intermittent condition:
^ A short to ground in the inflatable restraint front end discriminating sensor input circuit.
^ Cutting or chafing of front end discriminating sensor input circuit.

If any of the above conditions are found refer to Testing for Intermittent and Poor Connections in Diagram.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table:
4. This test checks for a malfunctioning discriminating sensor.
6. This test checks for a short-to-ground front end discriminating sensor input circuit.