GMC Sierra Owners Manual
Ultrasonic Parking Assist
If available, the Ultrasonic Rear Parking Assist (URPA) system assists the driver with parking and avoiding objects while in R (Reverse). URPA operates at speeds less than 8 km/h (5 mph).
The sensors on the rear bumper detect objects up to 2.5 m (8 ft) behind the vehicle, and at least 25 cm (10 in) off the ground.
The URPA system does not detect pedestrians, bicyclists, animals, or any other objects located below the bumper or that are too close or too far from the vehicle. To prevent injury, death, or vehicle damage, even with URPA, always check behind the vehicle and check all mirrors before backing.
How the System Works
URPA comes on automatically when the shift lever is moved into R (Reverse). A single tone sounds to indicate the system is working.
URPA operates only at speeds less than 8 km/h (5 mph).
An obstacle is indicated by audible beeps. The interval between the beeps becomes shorter as the vehicle gets closer to the obstacle.
When the distance is less than 30 cm (12 in) the beeping is a continuous tone for five seconds.
To be detected, objects must be at least 25 cm (10 in) off the ground and below tailgate level. Objects must also be within 2.5 m (8 ft) from the rear bumper. This distance may be less during warmer or humid weather.
Turning the System On and Off
The URPA system can be turned on and off using the rear park aid disable button located next to the radio.
The indicator light comes on when the system is disabled and turns off when the system is on.
When the system is off, PARK ASSIST OFF displays on the Driver Information Center (DIC). The message disappears after a short period of time.
URPA defaults to the on setting each time the vehicle is started.
Notice: If you use URPA while the tailgate is lowered, it may not detect an object behind your vehicle, and you might back into the object and damage your vehicle. Always verify the tailgate is closed when using URPA or turn off URPA when driving with the tailgate lowered.
When the System Does Not Seem to Work Properly
The following messages may be displayed on the DIC:
SERVICE PARK ASSIST: If this message occurs, take the vehicle to your dealer to repair the system.
PARK ASST BLOCKED SEE OWNERS MANUAL: This message can occur under the following conditions:
• The ultrasonic sensors are not clean. Keep the vehicle's rear bumper free of mud, dirt, snow, ice, and slush. For cleaning instructions, see Exterior Care on page 10‑102.
• The park assist sensors are covered by frost or ice. Frost or ice can form around and behind the sensors and may not always be seen; this can occur after washing the vehicle in cold weather. The message may not clear until the frost or ice has melted.
• A trailer was attached to the vehicle, or an object was hanging out of the tailgate during the last drive cycle. Once the object is removed and the tailgate is raised, URPA will return to normal operation.
• A tow bar is attached to the vehicle.
• The bumper is damaged. Take the vehicle to your dealer to repair the system.
• Other conditions, such as vibrations from a jackhammer or the compression of air brakes on a very large truck, are affecting system performance.