Vision V6-3.5L VIN F (1997)
Air Bag Control Module: Description and Operation
DESCRIPTION
The Airbag Control Module (ACM) contains the safing sensor and energy reserve capacitor. The ACM is mounted on the tunnel floor pan forward
of the center console. The safing sensor is located inside the ACM.
OPERATION
The safing sensor provides confirmation of a crash, but does not discriminate severity. The ACM monitors the system to determine the system
readiness. The ACM will store sufficient energy to deploy the airbags for only two minutes after the battery is disconnected. The ACM contains
on-board diagnostics, and will illuminate the AIRBAG warning lamp in the cluster when a fault occurs. The warning equipment is tested for a few
seconds every time the vehicle is started.
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.
