DTC 31

Test S: DTC 31 Driver Loop Energy Reserve Feed Open:

Supplemental Inflatable Restraint (SIR):

OPERATION:
During the "Continuous Monitoring" tests the DERM monitors the voltage at "Driver Source Sense" terminal "A5." When the circuit is operating normally, the measured voltage will be slightly less than "Driver 36 VLR." If the "Driver 36 VLR" circuit opens, the voltage measured at "Driver Source Sense" will decrease to slightly less than "Ignition 1" voltage. When voltage measured at "Driver Source Sense" is within a specified range of "Ignition 1" for 500 milliseconds DTC 31 is set.

Test Conditions: Tested every 100 milliseconds during "Continuous Monitoring" tests.

Failure Conditions: DTC 31 will set when the voltage measured at "Driver Source Sense" terminal "A5" is within a specified range of "Ignition 1" for 500 milliseconds.

Action Taken: DERM turns "ON" the "INFLATABLE RESTRAINT" warning lamp and sets a Diagnostic Trouble Code.

Conditions to Clear: DTC 31 will clear when the voltage measured at "Driver Source Sense" terminal "A5" is outside the specified range of "Ignition 1" which sets the Diagnostic Trouble Code, for 500 milliseconds.

POSSIBLE CAUSES:
Test Description: Number(S) below refer to circled number(S) on the diagnostic chart.
1. This test checks for an open in the "Driver 36 VLR" circuit.
2. This test checks for a short from the "Driver Source Sense" circuit to B+.
3. This test checks for high resistance in the "Driver Source Sense" circuit.
4. This test determines whether the malfunction is due to a malfunction within the dual pole arming sensor.

DIAGNOSTIC AIDS:
An intermittent condition is likely to be caused by a poor connection at arming sensor terminal "B" or "D," poor connection at DERM terminal "A4" or "A5," an open in CKTs 236 or 1400, or an open inside the dual pole arming sensor.