Tracer L4-110 1.8L DOHC (1995)
Air Bag Control Module: Description and Operation
Air Bag Diagnostic Monitor
Performing system diagnostics is the main purpose of the diagnostic monitor.
The air bag diagnostic monitor continually monitors all air bag system components and wiring connections for possible faults in the system. If the
diagnostic monitor detects a fault in the air bag system when the ignition switch is in the ON position, a diagnostic trouble code will be displayed
through the air bag warning indicator, located in the instrument cluster.
The air bag diagnostic monitor does not deploy the air bags in the event of a crash. The radiator primary crash front air bag sensors are "hard wired" to
the air bags; therefore, the radiator primary crash front air bag sensors and the LH kick panel safing rear air bag sensor and bracket determine when to
deploy the air bag modules.
Diagnostic Monitor Features and Functions
The air bag diagnostic monitor illuminates the air bag warning indicator for approximately six seconds when the ignition switch is in the ON position
and then turns the air bag warning indicator off. This shows that the air bag warning indicator is operational. If the air bag warning indicator does not
illuminate or the warning indicator stays on or flashes at any time, a fault has been detected by the air bag diagnostic monitor.
Diagnostic trouble codes may not be displayed for approximately 16 seconds after the ignition switch is placed in the ON position. This is the amount
of time the air bag diagnostic monitor requires to perform all tests and verify system faults, if present.
Diagnostic trouble codes are displayed as a series of flashes and pauses of the air bag warning indicator. Each diagnostic trouble code (series of
flashes) represents a two-digit number. For example, a diagnostic trouble code 32 is displayed as follows:
-
Three flashes, followed by a one second pause, then two flashes, followed by a three second pause.
-
Three flashes, followed by a one second pause, then two flashes, followed by a three second pause.
If a system fault is present and the air bag warning indicator is malfunctioning, an audible tone will be heard, indicating that system service is required.
The tone is a series of five sets of five beeps. This does not indicate a diagnostic trouble code 55. If the tone is heard, the air bag warning indicator is
inoperative and a system fault that requires service is present.
CAUTION: The thermal fuse does not blow (open) because of excessive current flowing through It. DO NOT attempt to jumper out the thermal fuse
with a circuit breaker or any other type of fuse.
If a fault exists that makes unwanted air bag deployment possible, the air bag diagnostic monitor has an internal thermal fuse that will blow (open)
automatically. This removes all power to the air bag deployment circuit. The air bag warning indicator will flash the appropriate diagnostic trouble
code to indicate the suspect circuit.
Diagnostic trouble codes are prioritized numerically so that if two or more different codes occur at the same time, the code having the highest priority
will be displayed first. After that code has been corrected, the next highest priority code will be displayed. The code will repeat continuously.
WARNING: THE BACKUP POWER SUPPLY ENERGY MUST BE DEPLETED BEFORE ANY AIR BAG COMPONENT SERVICE IS
PERFORMED. TO DEPLETE THE BACKUP POWER SUPPLY ENERGY, DISCONNECT THE BATTERY GROUND CABLE AND
WAIT ONE MINUTE.
The air bag diagnostic monitor includes an internal backup power supply. This feature provides sufficient backup power to deploy the air bags in the
event that the battery or battery cables are damaged in an accident before the forward air bag sensors and the LH kick panel safing rear air bag sensor
and bracket close. The backup power supply will deplete its stored energy approximately one minute after the battery ground cable is disconnected.
