B0018

CIRCUIT DESCRIPTION

SIR Schematics:

The inflatable restraint IP module deployment loop consists of an inflatable restraint IP module, the IP module - high control circuit, and the IP module - low control circuit. A shorting bar is used in the inflatable restraint IP module connector which will short together the IP module - high control and IP module - low control circuits when the connector is disconnected. This will help to prevent unwanted deployment of the inflator module during servicing. When the ignition is turned ON, the inflatable restraint Sensing And Diagnostic Module (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 DTC will be stored.

CONDITIONS FOR RUNNING THE DTC
Ignition 1 Voltage is within the normal operating voltage range.

CONDITIONS FOR SETTING THE DTC
The DTC will set if one of the following conditions occurs:
^ The IP module - high control input is more than 6 volts for 300 milliseconds.
^ The IP module - high control input is less than 2 volts and IP module deployment loop resistance is less than 6 ohms for 300 milliseconds.

ACTION TAKEN WHEN THE DTC SETS
The SDM commands the AIR BAG Indicator ON 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.

DIAGNOSTIC AIDS
Thoroughly inspect the wiring and the connectors. An incomplete inspection of the wiring and the connectors may result in a misdiagnosis, causing a part replacement with the reappearance of the malfunction.

The following are possible causes of the malfunction:
^ A short to ground or a short to voltage in the IP module - high control or the IP module - low control circuits.
^ A malfunctioning inflatable restraint IP module.
^ An internal SDM malfunction.

If an intermittent malfunction exists, refer to Testing for Intermittent and Poor Connections in Diagrams.

TEST DESCRIPTION

Steps 1-3:

Steps 4-10:

The number(s) below refer to the step number(s) on the diagnostic table.
4. Tests to see if the malfunction is intermittent
5. Tests to see if the malfunction is caused by the inflatable restraint IP module
8. Tests for a short to ground or voltage in the IP module - high control and IP module - low control circuits