Faulty Liftgate Object Sensors
Liftgate Object Sensors harness is open or shorted
Liftgate Object Sensors circuit poor electrical connection
Faulty Liftgate Control Module
Engine Light ON (or Service Engine Soon Warning Light)
The liftgate object sensors are pressure sensitive touch tapes located on either side of the upper inside edge of the liftgate panel. The two liftgate object sensors are placed in series between the liftgate object sensor signal circuit and the liftgate object low reference circuit. Each object sensor has a resistor as well as a switch. The resistors enable the liftgate control module to perform diagnostic functions on the circuits. When both liftgate object sensors are not pressed, the 5 volt reference voltage supplied by the liftgate control module passes through the resistors and the liftgate control module detects approximately 3.3 volts. Pressing a liftgate object sensor will cause the voltage to drop to approximately to 2.5 volts indicating an obstruction is present. If the liftgate is in the open position, the liftgate control module will prohibit liftgate movement. If the obstruction occurs during the power close function, the liftgate control module will command the liftgate to reverse direction.