Vision V6-215 3.5L SOHC (1995)
Air Bag Control Module: Description and Operation
OPERATION
The deceleration or g-force resulting from the impact of a front-end collision causes the safing sensor inside of the Airbag Control Module (ACM)
to be closed. As soon as one front sensor and the safing sensor are closed, an electrical charge is sent to the air bag module(s). This causes the
inflators to be actuated, thus deploying the air bags. The total time from the closure of the switches to deployment and deflation of the air bag is
1/10th of a second.
SELF DIAGNOSTIC FUCTIONS
Whenever the ignition key is turned to the "RUN" or "START" position, the air bag control module (ACM) performs a lamp check by turning the
AIR BAG warning lamp ON.
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The lamp stays lit for 6 to 8 seconds, then goes off. If the lamp remains off, it means that the ACM has checked the system and found it to be
free of discernible malfunctions. The air bag system is monitored by the ACM.
The ACM monitors critical input and output circuits within the air bag system, making sure they are operating correctly.
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Some circuits are tested continuously; others are checked only under certain circumstances. The ACM provides diagnostic information about
the air bag system to the technician through the DRB via the CCD bus.
CIRCUIT OPERATION
Two different circuits supply battery voltage from the junction block to the Airbag Control Module (ACM), they are F14 and F23. The F14 and
F23 circuits are connected to separate bus bars internal to the junction block. Different circuits from the Power Distribution Center (PDC) and the
ignition switch supply battery voltage to the junction block bus bars.
The F23 circuit supplies battery voltage to the ACM only when the ignition switch is in the RUN position. The F14 circuit powers the ACM when
the ignition switch is in either the START or RUN position.
A bus bar internal to the ignition switch connects the A1 circuit from the PDC to the A21 circuit when the switch is in either the START or RUN
position. The A21 circuit supplies battery voltage to the junction block bus bar that feeds the F14 circuit. A 20 Amp fuse in the PDC, cavity A,
protects the A1 and A21 circuits. A 10 Amp fuse in cavity 19 of the junction block protects the F14 circuit.
When the ignition switch is in the RUN position, it connects the A2 circuit from the PDC to the A22 circuit. The A22 circuit supplies battery
voltage to the junction block bus bar that feeds the F23 circuit. A 40 Amp fuse in cavity J of the PDC protects the A2 and A22 circuits. A 10 Amp
fuse in cavity 7 of the junction block protects the F23 circuit.
The ACM has a case ground, and an external dedicated ground, circuit Z2. The dedicated ground connects to the ACM bracket.
