LEMON Manuals: Even more car manuals for everyone
Home >> Ford >> 2021 >> Edge ST-Line, FWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Collision/Avoidance >> Parking Aid - Vehicles With: Active Park Assist >> Description And Operation >> Parking Aid - System Operation and Component Description >> System Operation

System Operation

Active Park Assist 

System Diagram 

GFD597166Courtesy of FORD MOTOR COMPANY

Network Message Chart PAM Network Input Messages 

Broadcast Message Originating Module Message Purpose
ABS active ABS module Disables the active park assist if an ABS activation occurs.
Active park assist steering angle control status PSCM Provides the steering angle status confirmation to the PAM
Ambient air temperature PCM Used to temperature compensate the active park assist sensor inputs.
EPAS failure PSCM Disables the active park assist if an EPAS failure occurs.
Gear lever position PCM Used to determine the current gear selection.
Parking aid settings APIM Allows the driver to change the parking aid settings through the centerstack infotainment display.
Stability-traction control indicator request ABS module Disables the active park assist if a stability or traction control system activation occurs.
Steering column torque PSCM Used to detect driver torque input and to disable the active park assist system if the driver intervenes by applying rotational torque to steering wheel during and active park assist maneuver.
Steering wheel angle ABS module Used to determine the current steering angle.
Trailer lamp connected TRM Disables the active park assist if a trailer is electrically connected to the vehicle.
Turn signal switch status SCCM Determines which side of the vehicle the intended parking space is located on.
Vehicle speed PCM Disables the active park assist system if the vehicle speed exceeds a preset threshold when the system is active.
Wheel speed and rotation data ABS module Used to confirm vehicle movement and calculate distance traveled during active park assist maneuvers.

PSCM Network Input Messages 

Broadcast Message Originating Module Message Purpose
Active park assist steering angle request PAM Used to command the steering angle during active park assist maneuvers.
Active park assist steering activation request PAM Request PSCM to allow the PAM to take control of the steering angle.
Vehicle speed PCM Disables active park assist if vehicle speed is too high during a maneuver.
Steering wheel angle ABS module Used to determine the current steering angle.

IPC Network Input Messages 

Broadcast Message Originating Module Message Purpose
Parking aid chime request PAM Used to command audio prompts during active park assist maneuvers.
Parking aid fault status PAM Used by IPC to display the active park assist fault messages to the driver.

APIM Network Input Messages 

Broadcast Message Originating Module Message Purpose
Active park assist messages PAM Used to generate driver instructions through the centerstack infotainment display during active park assist maneuvers.
Parking aid fault status PAM Used by the centerstack infotainment display to display the active park assist fault messages to the driver.

Active Park Assist (if equipped) 

NOTE: Aftermarket or modified audio systems may disable necessary audible warnings.

The PAM communicates with several modules to control the functions of the active park assist system. The PAM utilizes steering angle, vehicle wheel rotation count and direction, active park assist sensor inputs, parking aid sensor inputs, vehicle speed and transmission selection to calculate vehicle position and distance in relation to the parking space. The inputs are used by the PAM to command the steering angles required to maneuver the vehicle into or out of a parallel parking space or into a perpendicular parking space.

When the active park assist switch is pressed, a ground signal is provided to the PAM to activate the active park assist system. The PAM uses active park assist sensor inputs, parking aid sensor inputs, vehicle speed and transmission selection to determine if the operator is attempting to maneuver the vehicle into or out of a parallel parking space or into a perpendicular parking space.

Pressing and releasing the active park assist switch at any time during an active park assist maneuver disables the active park assist system. If the system is disabled by the operator after the system starts to control the steering, the centerstack infotainment display displays an active park assist canceled message followed by a warning chime.

The PAM continuously monitors the active park assist sensor signals any time the ignition is on. When no signal is detected from an active park assist sensor, the PAM sets a DTC.

If an input module fault or other system malfunction is present, the active park assist system is disabled. An active park assist fault message is shown on the centerstack infotainment display and a DTC is set in the PAM. In addition to possible vehicle faults, certain driver actions and vehicle operating conditions can cause the active park assist system to be temporarily disabled.

Certain conditions can cause the active park assist system to incorrectly align the vehicle in the parking space:

NOTE: The active park assist system is disabled when a trailer is electrically connected to the vehicle.

Parallel Parking Operation 

After the active park assist system is activated and the PAM has determined the driver is attempting to maneuver the vehicle into a parallel parking space (the active park assist switch is pressed once), the PAM begins searching for a parking space using the front active park assist sensors. The multifunction switch turn signal input from the SCCM determines the side of the vehicle that the PAM searches for a parking space. When a side is selected with the turn signal, the PAM searches on that side of the vehicle until the active park assist is switched off, the ignition is cycled, or the opposite side is selected by the driver. By default, the PAM searches for spots on the passenger side of the vehicle.

The system measures the available parking spaces and its surroundings as the operator drives by to determine if the vehicle can be maneuvered into the available parking space. The PAM uses inputs from the front active park assist sensors and the wheel speed and rotation data message to find an acceptable parking space. After a space has been located, a chime is sounded through the audio system and the centerstack infotainment display shows a message informing the driver that a parking space has been located on the left or right side and requesting the driver to pull forward to park. After the driver moves the vehicle forward to the appropriate start position, as determined by the PAM, the system requests the driver to stop, shift the transmission into reverse and remove hands from the steering wheel. After the transmission is in reverse and no driver input torque on the steering wheel is detected (driver has removed their hands from the wheel), the active park assist system takes control of the steering and prompts the driver to begin backing into the parking space. The active park assist system sounds tones through the audio system and issues commands through the centerstack infotainment display instructing the driver to back up and pull forward as necessary while the system controls the steering to position the vehicle within the detected parking space. The operator maintains full control of the gear shifting, accelerator and brakes during active park assist maneuvers.

The PAM determines that the parallel parking maneuvers are completed based on the final vehicle alignment. The vehicle should be located approximately 0 to 30 cm (12 in) from the street curb if a curb is detected, otherwise the system aligns the vehicle to the slot end object. When the active park assist maneuver is complete, the centerstack infotainment display displays an active park assist finished message followed by an audible chime.

Park Out Assist Operation 

NOTE: The park out assist system is only for exiting parallel spots.

Parking out assist is available immediately after a parallel park was completed, or after an ignition on. The driver must activate the park assist system by pressing the active park assist switch once then select a side to exit the parking spot using the turn signal before the system measures the location to park out of. Once the turn signal status is received from the SCCM, the PAM verifies the indicated side is clear by analyzing the clearance around the vehicle using input from the active park assist sensors and the parking aid sensors. When the indicated side is clear of obstructions, the centerstack infotainment display shows a message informing the driver to remove hands from the steering wheel and shift to drive (D or S) or reverse gear, depending on the detected clearances to the front and rear of the vehicle. The system then requests the driver to move the vehicle forward or reverse to position the vehicle within the space. When the PAM detects that the vehicle has been moved to the requested position, the centerstack infotainment display shows a message informing the driver to stop and shift to drive (D or S). After the transmission is shifted and no driver input torque on the steering wheel is detected (driver has removed their hands from the wheel), the PAM sends the active park assist steering angle request to the PSCM to turn the wheels to an angle which steers the vehicle out of the parallel parking space on the desired side. When the desired steering angle is achieved, the active park assist system sounds tones through the audio system and issues commands through the centerstack infotainment display instructing the driver to pull forward. The driver may be prompted to shift back and forth multiple times depending on parking spot size for the system to successfully guide the vehicle out of the spot.

The PAM determines that the park out assist maneuvers are complete when a clear path to exit the parking space is detected. When the maneuver is complete, a chime is played and the centerstack infotainment display shows a message informing the driver to take control of the steering. It remains the responsibility of the driver to check for safe conditions when entering traffic from a parking space.

Perpendicular Parking Operation 

After the active park assist system is activated and the PAM has determined the driver is attempting to maneuver the vehicle into a perpendicular parking space (the active park assist switch is pressed twice), the PAM begins searching for a parking space using the front active park assist sensors. The multifunction switch turn signal input from the SCCM determines the side of the vehicle that the PAM searches for a parking space. If the turn signal is not active, the PAM defaults to searching on the passenger side of the vehicle.

The system measures the available parking spaces and its surroundings as the operator drives by to determine if the vehicle can be maneuvered into the available parking space. The PAM uses inputs from the front active park assist sensors and the wheel speed and rotation data message to find an acceptable parking space. After a space has been located, a chime is sounded through the audio system and the centerstack infotainment display shows a message informing the driver that a parking space has been located on the left or right side and requesting the driver to pull forward to park. After the driver moves the vehicle forward to the appropriate start position, as determined by the PAM, the system requests the driver to stop, shift the transmission into reverse and remove hands from the steering wheel. After the transmission is in reverse and no driver input torque on the steering wheel is detected (driver has removed their hands from the wheel), the active park assist system takes control of the steering and prompts the driver to begin backing into the parking space. The active park assist system sounds tones through the audio system and issues commands through the centerstack infotainment display instructing the driver to back up and pull forward as necessary while the system controls the steering to position the vehicle within the detected parking space. The rear side sensors are used to re-measure the parking spot when the vehicle is backing into the perpendicular spot. This is done to improve measurement accuracy, and allows for trajectory corrections to be made mid-park, if needed. The operator maintains full control of the gear shifting, accelerator and brakes during active park assist maneuvers.

The PAM determines that the perpendicular parking maneuvers are completed based on the final vehicle alignment. The perpendicular parking aid system attempt to center the vehicle between the two vehicles and align the end vehicle angle with the angle of the parked vehicles. If only one vehicle is detected, the system align with that vehicle at a distance of 65 to 80 cm (26 to 32 in). When the active park assist maneuver is complete, the centerstack infotainment display displays an active park assist finished message followed by an audible chime.

Parking Aid System 

The active park assist system uses input from the audible parking aid system when parking the vehicle. Input from the front and rear parking aid sensors help the PAM to determine the position of the vehicle in the parking space. For more information on the operation of the operation of the audible parking aid system, Refer to: Parking Aid - System Operation and Component Description .

EPAS Control 

The PSCM controls the steering during active park assist maneuvers based on the active park assist steering angle request message received from the PAM. The PSCM also provides steering column torque data to the PAM to determine if the driver has placed their hand(s) on the steering wheel while the active park assist system has control of the steering.

Active Park Assist Chimes 

The active park assist system chimes are controlled by the IPC. Based on the parking aid chime request message received from the PAM, the IPC prioritizes the incoming chime request and then commands the ACM (for vehicles without Sony® audio system) or the DSP (for vehicles with Sony® audio system) to sound the chime through the audio system speakers. In the event of an audio system fault, the IPC sounds the chimes through an integral speaker. Refer to: INSTRUMENTATION, MESSAGE CENTER AND WARNING CHIMES

Active Park Assist Message Display 

Active park assist messages are shown on the centerstack infotainment display. Conditions that can cause the active park assist system to be temporarily unavailable or cause the current active park assist system maneuver to be cancelled are:

NOTE: For active park assist fault message in the infotainment display, consult the diagnosis and testing PAM symptom chart  .
Cancellation Event FDIM Message/Audio Chime
Vehicle speed above 18 mph (29 km/h) during the measuring/searching phase for 30 consecutive seconds. Note, the screen is shown while driving faster than 18 mph (29 km/h), screen goes away and system deactivates after 30 seconds. PARALLEL PARK REDUCE SPEED TO SCAN FOR PARKING SPOT
Deactivation of the AdvanceTrac® system by the driver while the active park assist system is currently scanning for parking slots. ACTIVE PARK ASSIST NOT AVAILABLE REFER TO OWNER GUIDE followed by a chime
A vehicle attachment is detected by the reverse parking aid system, such as a trailer or bike rack. The attachments need to be electrically connected to the vehicle to prevent the active park assist from activating. ACTIVE PARK ASSIST NOT AVAILABLE REFER TO OWNER GUIDE followed by a chime
Driver grabbing steering wheel while the active park assist system has control of the steering. ACTIVE PARK ASSIST CANCELLED BY DRIVER followed by a chime
The driver changes from reverse to drive before the vehicle is far enough inside the parking space.
Vehicle speed above 6 mph (10 km/h) when the active park assist system has control of the steering. ACTIVE PARK ASSIST DEACTIVATED followed by a chime
Deactivation of the AdvanceTrac® system by the driver while the active park assist system has control of the steering.
An ABS activation or an AdvanceTrac® system activation occurs while the active park assist system has control of the steering.
Maximum number of moves is exceeded during any parking maneuver. The move number is incremented each time the driver shifts gears, 9 is the maximum.