B0091

CIRCUIT DESCRIPTION
When the ignition is turned ON, the Inflatable Restraint Sensing And Diagnostic Module (SDM) performs tests to diagnose critical malfunctions within the SIR system. The SDM monitors the IP module disable switch-signal and IP module disable switch indicator- control circuits in order to determine whether or not to disable the inflatable restraint IP module. The SDM also monitors the IP module disable switch-signal and the IP module disable switch indicator- control circuits for an open, high resistance, short to ground or short to voltage condition.

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

CONDITIONS FOR SETTING THE DTC
^ The PSIR switch must be in the OFF position.
^ The voltage detected in the IP module disable switch-signal circuit is less than 1 volt.
^ The voltage detected in the IP module disable switch indicator-control circuit is greater than 1 volt.

ACTION TAKEN WHEN THE DTC SETS
^ The SDM defaults to the OFF position, disabling the IP module.
^ The SDM attempts to turn the inflatable restraint IP module disable switch indicator ON and OFF every 5 seconds.
^ 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 misdiagnosis, causing a part replacement with the reappearance of the malfunction.

The following are possible causes of the malfunction:
^ An open or a high resistance in the IP module disable switch-signal circuit
^ An open or a high resistance in the IP module disable switch indicator-control circuit
^ A short between the IP module disable switch- signal and IP module disable switch indicator-control circuits
^ Damage or corrosion on the IP module disable switch harness connector
^ Damage or corrosion on the IP module disable switch harness connector
^ Damage or corrosion on the SDM harness connector
^ An internal IP module disable switch malfunction
^ An internal IP module disable switch indicator malfunction
^ An internal SDM malfunction

If an intermittent condition exists, Refer to Diagnostic Aids for Circuit Testing and Wiring Repair procedures.

TEST DESCRIPTION

Steps 1-10:

Steps 11-15:

The numbers below refer to the step numbers on the diagnostic table:
6. This step tests to see if the IP module disable switch indicator is damaged.
9. This step tests to see if there is an open or high resistance in the IP module disable switch- signal circuit.
10. This step tests to see if there is an open or high resistance in the IP module disable switch indicator-control circuit.
11. This step test to see if there is a short between the IP module disable switch-signal and the IP module disable switch indicator-control circuits.