Trunk / Liftgate: Description and Operation
AUTOMATIC BACK DOOR SYSTEMSystem Description
The automatic back door system consists of a one piece unit that combines the back door control unit along with the back door motor, back door clutch and the back door encoder. The back door latch contains a lock function that can control the two functions of automatic back door latch closure and electrical opener with a single motor when you close the back door to the halfway-state.
- Back door auto closure
When the back door is closed to the halfway state (half-latch) position, the motor automatically drives to rotate the latch lever and pull it in from half latched to full latched.
- Power back door
With the back door closed, press the power liftgate switch or press the remote keyless entry button, or pull the back door handle with the back door unlocked, the back door latch motor opens the locking plate and releases the latch. The back door motor then raises the door to the full open position.
With the back door fully open, press the power liftgate switch, remote keyless entry button or the back door close switch, the back door motor closes the door to the half-latch state. The back door latch motor then drives the latch to the full close position.
At the onset of each power open or power close application, the hazard lamps will flash 3 times and the warning chime will sound 3 times lasting a total of 2 seconds.
OPERATION DESCRIPTION
Power Liftgate Switch Operation (Fully Closed -> Fully Open Operation)
- When the power liftgate switch is pressed, back door control unit terminal 23 receives the signal.
- The back door control unit checks the A/T selector lever (P position) through terminal 18, vehicle speed through terminal 21, ignition status through terminal 7, glass hatch is closed through terminal 17 and battery voltage is present through terminal 3.
- When the back door control unit receives the signal, if the auto back door operating enable conditions are met, it sends a 5 volt signal through terminal 6 and grounds terminal 9 to sound the warning chime, sends a signal to the BCM through terminal 4 to flash the hazard lamps and unlocks the back door latch through terminal 12.
- The back door control unit supplies power to the magnetic clutch and the back door motor and moves the back door in the open direction. (At this time, it also executes speed control, input reverse, and anti-pinch detection control.)
- When the back door is opened to the full-open position, the full-open position is detected by the encoder, and the back door control unit switches the back door motor OFF and the magnetic clutch is pulsed and then turned OFF.
- The back door is held in the fully open position by the gas stays.
Remote Keyless Entry Operation (Fully Closed -> Fully Open Operation)
- When the remote keyless entry button is pressed for at least 0.5 seconds, back door control unit terminal 21 receives the signal.
- The back door control unit checks the A/T selector lever (P position) through terminal 18, vehicle speed through terminal 21, ignition status through terminal 7, glass hatch is closed through terminal 17 and battery voltage is present through terminal 3.
- When the back door control unit receives the signal, if the auto back door operating enable conditions are met, it sends a 5 volt signal through terminal 6 and grounds terminal 9 to sound the warning chime, sends a signal to the BCM through terminal 4 to flash the hazard lamps and unlocks the back door latch through terminal 12.
- The back door control unit supplies power to the magnetic clutch and the back door motor and moves the back door in the open direction. (At this time, it also executes speed control, input reverse, and anti-pinch detection control.)
- When the back door is opened to the full-open position, the full-open position is detected by the encoder, and the back door control unit switches the back door motor OFF and the magnetic clutch is pulsed and then turned OFF.
- The back door is held in the fully open position by the gas stays.
Back Door Handle Switch Operation (Fully Closed -> Fully Open Operation)
- When the back door handle is pulled, back door control unit terminal 26 receives the signal.
- The back door control unit checks that the back door is unlocked and checks the A/T selector lever (P position) through terminal 18, vehicle speed through terminal 21, ignition status through terminal 7, glass hatch is closed, battery voltage and back door close switch position through terminal 13.
- When the back door control unit receives the signal, if all auto back door operating enable conditions are met, it sends a 5 volt signal through terminal 6 and grounds terminal 9 to sound the warning chime, sends a signal to the BCM through terminal 4 to flash the hazard lamps and unlocks the back door latch through terminal 12.
- The back door control unit supplies power to the magnetic clutch and the back door motor and moves the back door in the open direction. (At this time, it also executes speed control, input reverse, and anti-pinch detection control.)
- When the back door is opened to the full-open position, the full-open position is detected by the encoder, and the back door control unit switches the back door motor OFF and the magnetic clutch is pulsed and then turned OFF.
- The back door is held in the fully open position by the gas stays.
Power Liftgate Switch Operation (Fully Open -> Fully Closed Operation)
- When the power liftgate switch is pressed, the back door control unit terminal 23 receives the signal.
- The back door control units checks door position through the rotary encoder.
- When the back door control unit receives the signal, if the auto back door operating enable conditions are met, it sends a signal through terminal 6 and grounds terminal 9 to sound the warning chime and sends a signal to the BCM through terminal 4 to flash the hazard lamps.
- The back door control unit supplies power to the magnetic clutch and the back door motor and move the back door in the close direction. (At this time, it also executes speed control, input reverse, and anti-pinch detection control.)
- When the back door reaches the half-latch state, the half-latch switch detects this and the signal is sent to the back door control unit terminal 22.
- When the back door control unit receives the half latch switch signal, it switches OFF the back door motor and the magnetic clutch and operates the cinch latch motor.
- When the back door latch operates and full close is detected through terminal 14 of the back door control unit, the cinch latch motor reverses to the neutral position and the back door auto closure operation ends and the door is fully closed.
Remote Keyless Entry Operation (Fully Open -> Fully Closed Operation)
- When the remote keyless entry switch is pressed for at least 0.5 seconds, the back door control unit terminal 21 receives the signal.
- The back door control units checks door position through the rotary encoder.
- When the back door control unit receives the signal, if the auto back door operating enable conditions are met, it sends a signal through terminal 6 and grounds terminal 9 to sound the warning chime and sends a signal to the BCM through terminal 4 to flash the hazard lamps.
- The back door control unit supplies power to the magnetic clutch and the back door motor and move the back door in the close direction. (At this time, it also executes speed control, input reverse, and anti-pinch detection control.)
- When the back door reaches the half-latch state, the half-latch switch detects this and the signal is sent to the back door control unit terminal 22.
- When the back door control unit receives the half latch switch signal, it switches OFF the back door motor and the magnetic clutch and operates the cinch latch motor.
- When the back door latch operates and full close is detected through terminal 14 of the back door control unit, the cinch latch motor reverses to the neutral position and the back door auto closure operation ends and the door is fully closed.
Back Door Close Switch Operation (Fully Open -> Fully Closed Operation)
- When the back door close switch is pressed, the back door control unit terminal 8 receives the signal.
- The back door control units checks back door disable switch terminal 13 status and door position (must be fully opened), through rotary encoder and battery voltage.
- When the back door control unit receives the signal, if the auto back door operating enable conditions are met, it sends a signal through terminal 6 and grounds terminal 9 to sound the warning chime and sends a signal to the BCM through terminal 4 to flash the hazard lamps.
- The back door control unit supplies power to the magnetic clutch and the back door motor and move the back door in the close direction. (At this time, it also executes speed control, input reverse, and anti-pinch detection control.)
- When the back door reaches the half-latch state, the half-latch switch detects this and the signal is sent to the back door control unit terminal 22.
- When the back door control unit receives the half latch switch signal, it switches OFF the back door motor and the magnetic clutch and operates the cinch latch motor.
- When the back door latch operates and full close is detected through terminal 14 of the back door control unit, the cinch latch motor reverses to the neutral position and the back door auto closure operation ends and the door is fully closed.
Reversal
- If the power liftgate switch, remote keyless entry switch or the back door close switch is pressed during back door power open and close operation, the back door will reverse direction.
- If the outside handle switch is pulled during power open or power close, the power back door will automatically stop and go to manual mode.
Anti-Pinch Function
- During auto open or close operation, if an object is detected in the door's path, the back door operates in the reverse direction until fully closed or open to prevent pinching.
- During auto close operation, if an object is detected by the pinch strips in the door's path, the back door operates in the open direction until it is fully open.
- During auto cinch latch operation, if an object is detected by the pinch strips in the door's path, the back door operates depending on the back door disable switch position. If the back door disable switch is in the OFF position, the back door operates in the open direction until it is fully open. If the back door disable switch is in the ON position, the back door will reverse only until the latch is fully released.
- If the pinch strips are present but are not functioning properly (permanently sensing a pinch), the automatic back door system will operate in the open direction only.
- If the pinch strips are not connected to the automatic back door system, it will not operate.
Gas Stay Check
- During each power open operation, the back door control unit monitors motor current draw to determine if the gas stays are functioning properly.
- If a failure of the gas stays is detected, the back door control unit will close the back door while sounding the warning chime.
Warning Functions
- The warning chime is sounded according to the back door operating state, operations, and conditions.
Auto Back Door Operation Enable Conditions
Control When Operating Enable Conditions Not Met During Power Open/Close
Control When Operating Enable Conditions No Longer Met
Warning Chime Active Conditions
The warning chime uses two types of audio warnings, a friendly chime and a warning chime. The friendly chime consists of dings lasting 0.66 seconds each immediately followed by the next ding. The warning chime consists of beeps lasting 0.33 seconds with a pause of 0.33 seconds between each beep.
Reverse Conditions