Principles of Operation (How Does It Work?) Module Controlled

Power Door Locks
The central security module controls the power door lock and keyless entry system. The lock and unlock operation is carried out by supplying ground to the central security module from the door lock control switch. The normal path of the actuators is to ground through the central security module. The door lock control switch will lock and unlock all doors by grounding the appropriate circuit to the central security module. The central security module then supplies power to the appropriate common actuator circuit to lock or unlock all doors.

Keyless Entry
Keyless entry can be achieved through either the keyless entry keypad or keyless entry remote transmitter. The keyless entry keypad is wired directly to the central security module. Pressing a keyless entry keypad button supplies a ground signal to the central security module. When the correct sequence is received, the central security module will unlock the driver door. If the 3/4 is pressed within five seconds after the code entry, the central security module will unlock all doors. Pressing the 7/8 and 9/0 buttons will cause the central security module to lock the doors. The all-door lock and all door unlock functions are the same circuit and operation as pressing a door lock control switch to lock or unlock.

The keyless entry remote transmitter sends a frequency that is received by the central security module internal antenna. Depending on the frequency received, the central security module will lock all doors or unlock the driver door. If the unlock frequency is received again within five seconds of the first unlock, the central security module will unlock all doors. This function is the same as that for the keyless entry keypad.

If the frequency received is for the panic button, the central security module will cycle ground to the park lamp relay coil and horn relay coil. The park lamps and horn will continue to cycle until the panic button is pressed again or the ignition switch is turned to the RUN position.

Autolocks
The autolock function will automatically lock the doors when the correct conditions exist. The conditions monitored for autolock are: door ajar state, brake pedal position and vehicle speed. The central security module monitors these inputs and when all are correct the central security module will lock all the doors. For autolock to function, the central security module must see a door ajar signal go from ajar to closed. Then the central security module will monitor the brake switch circuit for the voltage to drop indicating the brake pedal is released. The central security module will then monitor vehicle speed. When vehicle speed reaches more than 5 km/h (3 mph), the central security module will lock all doors. The autolock function can be disabled if the customer desires. Refer to Autolock and Horn Chirp Programming for the correct procedure. Autolock and Horn Chirp Programming