Keyless Entry: Description and Operation

The keyless entry system consists of a portable remote control transmitter and a receiver mounted between the sun visors. System operation is based on a coded infrared signal from the transmitter to the receiver. The transmitter is programmed into the receiver providing the correct programming sequence is met.

When the keyless entry system is activated, the corresponding relay operates to supply voltage to the motors. The use of either relay determines the polarity of the voltage that is supplied to the door lock motors.

When the keyless entry system is used, the transmitter sends a signal to the keyless entry module. If the doors are unlocked, the module activates a transistor switch to apply voltage to the lock relay coil. The coil is energized to close the normally open contacts of the lock relay. Battery voltage from the relay is applied to the door lock motors to lock the doors. Current flows in the same path to ground as it does when the master door lock switch is used.

When the doors are locked, the keyless entry module applies voltage to the unlock relay coil and a similar action takes places to unlock the doors.

To activate the system, aim the transmitter diode toward the receiver and press the transmitter signal button to lock or unlock the doors as desired.

Effective transmitter range is 4.75 meters (15 ft.) with the transmitter positioned no more than 45 degrees from the receiver centerline.