Tribute ES 4WD V6-3.0L DOHC (2002)
Power Locks: Description and Operation
Troubleshooting (Security and Locks)
LOCKS, LATCHES AND ENTRY SYSTEMS
Principles of Operation
Power Door Locks
The generic electronic module (GEM) controls the power door lock and keyless entry system. Lock and unlock operation is achieved through the use of
internal relays in the GEM. The relays are all door lock, all door unlock and driver door unlock. The normal path of the relays is to ground.
Pressing the door lock control switch to lock or unlock sends a ground signal to the GEM. The same GEM pin is used for unlock and lock input. The
unlock signal is a direct connection to ground. The lock signal is altered by an internal resistor in the door lock control switch. This varied resistance
identifies lock or unlock command to the GEM.
The door locks can also be controlled by the door key cylinder switches. For the liftgate door lock switch, turning the key to lock or unlock sends a
ground signal to the GEM. The GEM will then ground the all door lock or all door unlock relay supplying voltage to the actuators. Turning the driver
door key cylinder to the lock position sends a ground signal to the GEM. The GEM will then ground the all door lock relay supplying voltage to the
actuators. Turning the driver door key cylinder to unlock sends a ground signal to GEM. The GEM will ground the driver door unlock relay and supply
voltage to only the driver door actuator. If a second unlock ground is received within three seconds of the first, the GEM will ground the all door unlock
relay supplying voltage to the passenger door actuators (if equipped with two stage unlock).
Keyless Entry
The keyless entry remote transmitter sends a signal that is received by the GEM internal antenna. Depending on the signal received, the GEM module
will ground the appropriate internal relay and lock all doors or unlock the driver door. If the unlock signal is received again within three seconds of the
first unlock, the GEM will ground the internal all door unlock relay unlocking all doors. The lock and unlock relay output to the actuators is controlled
by the GEM, the same as power door lock operation from the control switch.
If the signal received is for the panic button, the GEM will cycle ground to the park lamp relay coil, headlamp 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 or after the timer expires.
