DTC 54

Test AC: DTC 54 Passenger Side Low High Resistance:

Supplemental Inflatable Restraint (SIR):

OPERATION:
During the "Initiator Assembly Resistance Test", the DERM grounds the "Passenger Side Low" terminal "B7" and turns "ON" the driver current source at the "Driver Side High" terminal "B9." This causes a known amount of current to flow through the Driver Initiator Circuit allowing the resistance to be calculated. The normal, non-deployment current flow through the Passenger Deployment Loop is also affected since the DERM is supplying ground through a resistor bypassing the ground supplied by the resistance of the Discriminating Sensor Network. When the voltage difference between "Passenger Side High" terminal "A7" and "Passenger Side Low" terminal "B7" is above a specified value DTC 54 is set.

Test Conditions: Tested once each ignition cycle during the "Initiator Assembly Resistance Test" when: 1) No "higher priority faults" are detected during "Turn-ON", 2) No "higher priority faults" are detected during "Continuous Monitoring" for 1 second, 3) No "CRANK" signal present, 4) "Ignition 1" voltage is above a specified value.

Failure Conditions: DTC 54 will set when the voltage difference between "Passenger Side High" terminal "A7" and "Passenger Side Low" terminal "B7" is above a specified value.

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

Conditions to Clear: DTC 54 will clear each time the ignition switch is turned "OFF."

POSSIBLE CAUSES:
Test Description: Number(S) below refer to circled number(S) on the diagnostic chart.
1. This test determines whether the malfunction is due to a high resistance or open in the "Passenger Side Low" circuit between the DERM and the Passenger Inflator Module Harness Connector.

DIAGNOSTIC AIDS:
In intermittent condition is likely to be caused by a poor connection at DERM terminal "B7" or an open in CKT 1404A. The test for this diagnostic trouble code is run only while the "INFLATABLE RESTRAINT" warning lamp is performing the bulb check. When a scan tool "Clear Codes" command is issued and the malfunction is still present, the DTC will not reappear until the next ignition cycle.