2024 Edition

ASE L4 Practice Test

ASE identifies Advanced Driver Assistance Systems (ADAS) as an individual service area (L4). The ADAS specialist test involves the service and diagnosis of the following components:

• General ADAS

• Camera-based Systems

• Radar-based Systems
• Ultrasonic (Sonar)-based Systems

This free sample ASE L4 Practice Test below consists of questions organized within 4 sections.

Tests.com's ASE L4 Practice Test was written by Dr. John Kershaw, an ASE test prep expert: ASE test question developer; ASE Certified Master Technician; ASE Master Truck Technician; and Auto Industry Technical Instructor. Dr. Kershaw was among the first to receive ASE certification in 1972.

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General ADAS Service and Diagnosis

1.	Technician A says performing a pre-scan of the OBD-II system for trouble codes should be done before performing repair or calibration on an ADAS equipped vehicle. Technician B says performing a post-scan is a best-practice to verify repair and calibration are successful. Who is right?
		a. A only
		b. B only
		c. Both A and B
		d. Neither A nor B
Both technicians are correct. Tech A is correct because you need to check all control modules for diagnostic information before disconnecting the vehicle battery as information kept in keep-alive memory may be lost when power to the control modules is removed. The loss of this data could be costly after the repair, could delay repairs and could be dangerous if the vehicle is returned to the customer without a malfunctioning ADAS system. A pre-scan of the vehicle systems should be performed with a factory scan tool or equivalent OBD-II CAN aftermarket scan tool. The diagnostic trouble codes retrieved should be recorded on the RO. Tech B is correct because verifying the repair is part of a sound diagnostic strategy. Incorrect answer. Please choose another answer.

2.	Technician A says a road test of a vehicle is not needed if an ADAS calibration is successful. Technician B says a road test should be performed at the end of each ADAS repair or calibration to verify the calibration or system functionality. Who is right?
		a. A only
		b. B only
		c. Both A and B
		d. Neither A nor B
Tech B is correct because it is an industry best practice to verify that the ADAS system is working properly. You need to drive the vehicle and make sure all ADAS systems are functional and all visual, audible and haptic alerts are working. After the road test, scan all vehicle systems and be sure there are no DTC's for ADAS-related systems. Incorrect answer. Please choose another answer.

3.	Measurement and layout for an ADAS vehicle calibration begin with consulting the online service information to determine the calibration details. Some OEMs (Original Equipment Manufacturers) will require as much as 20 feet in front of a vehicle with no:
		a. Clutter backdrop
		b. Scan tool connected
		c. DTC Diagnostic Trouble Code) set
		d. Inclinometer used
A measurement and layout begin with consulting the online service information to determine the calibration considerations. Some manufacturers will require as much as 20 feet in front of a vehicle with a plain backdrop free of clutter. You will need a roll of masking tape, a marker or pen, and chalk on-hand for marking the floor and an inclinometer will be utilized to make sure the floor is level. Incorrect answer. Please choose another answer.

4.	For question 4, refer to the ASE L4 reference document using this link in a new tab: https://www.ase.com/dist/docs/ASE_L4_CV1_2022.pdf All of the following are correct on the ADAS Composite Vehicle 1 Blind Spot Warning (BSW) that detects vehicles in adjacent lanes to the rear and alerts drivers to their presence, EXCEPT:
		a. Left and right rear corner radar modules are the primary inputs.
		b. System can be turned OFF using the ADAS control panel switch.
		c. When the ignition switch is cycled from ON to OFF the System defaults to OFF
		d. Parameters can be adjusted using the infotainment display center.
Page 5 of Composite Vehicle 1 states that when the ignition switch is cycled from ON to OFF, the System defaults to ON, not OFF. Incorrect answer. Please choose another answer.

Camera-based Systems Service and Diagnosis

5.	Two technicians are discussing ADAS camera calibration. Technician A says that replacing a windshield will require calibration of the multifunction forward-facing camera. Technician B says a battery charger keeps a vehicle's battery charged during the ADAS system calibration. Who is right?
		a. A only
		b. B only
		c. Both A and B
		d. Neither A nor B
Tech A is correct because the ADAS system may need to be calibrated after the following service: Following windshield repair or replacement After a wheel alignment After repair or replacement of suspension or steering components Following collision repair damage When following a repair procedure or DTC that recommends or requires calibration When a customer complaint that could be considered a system malfunction is suspected Tech B is incorrect because a battery maintainer is used to keep a vehicle's battery charged during the ADAS system calibration, not a battery charger. A vehicle with doors or other accessories powered up for more than five minutes may begin to deplete the battery. Incorrect answer. Please choose another answer.

6.	A driver complains that the brakes seem to release slowly at times, usually when stopped on a hill. This is normal operation of which of the following ADAS systems?
		a. Hill start assist
		b. Pre-collision
		c. Adaptive cruise control
		d. Automatic emergency braking
The electronic brake control module (EBCM) calculates the brake pressure that is needed to hold the vehicle on an incline, and locks that pressure for a certain time by commanding the appropriate solenoid valves on and off when the brake pedal is released. Drivers are not aware that the vehicle is equipped with this system. As a result, when the brake pedal is released after being stopped on a hill, the brakes are slow to release. The other three ADAS systems will not do this action. Incorrect answer. Please choose another answer.

Radar-based Systems Service and Diagnosis

7.	An ADAS Radar unit is being calibrated. Which of the following tools is used to locate the vehicle centerline?
		a. Ruler
		b. Tape measure
		c. Slide rule
		d. Plumb bob
You must determine the centerline of the vehicle. A plumb bob is used to find the centerline by locating the center of the emblem in the front and rear of the vehicle and marking the center on the floor at the location of the plumb bob. Then, the vehicle's center line can be projected using a string or a laser level. Choosing an appropriate location to perform ADAS calibrations is vital. The shop should be well-lit with overhead lighting that is even and consistent. The shop floor should be level, as a slope to the floor could lead to improper calibrations. Incorrect answer. Please choose another answer.

8.	Calibrating radar involves all of the following, EXCEPT:
		a. Factory-level scan tool
		b. Special targets set at precisely specified location around the vehicle
		c. Both static (stationary) and dynamic (moving) calibration is used
		d. Driving the vehicle in a circle 6 times for camera calibration
Driving the vehicle in a circle will not properly locate the corners. Radar or camera calibration on an ADAS vehicle is required when one or more cameras are replaced on a mounting component, such as a windshield, bumper cover, mirror or door. The calibration is a shop static process. Patterned mats are located around the vehicle at specific locations and the scan tool is used to initiate the process. A factory-level scan tool is required on most ADAS dynamic calibration. Incorrect answer. Please choose another answer.

9.	For questions 9 and 10, refer to the ASE L4 reference document using this link in a new tab: https://www.ase.com/dist/docs/ASE_L4_CV1_2022.pdf The ADAS Composite Vehicle 1 Forward Radar Module assists in collision mitigation by evaluating closing rates of objects using radar waves to determine the distance to objects in the vehicle's path of travel. It is mounted in a non-adjustable, non-repairable bracket directly to the center of the front grille. Still, the base adjustment is done using adjustment screws on the forward radar module. Which screw provides a horizontal setting?
		a. Top Left
		b. Top Right
		c. Bottom Right
		d. Bottom Left
The illustration on page 8 of the Composite Vehicle 1 shows that the top left screw is the horizontal adjustment screw. B is incorrect because the top right screw is a fixed pivot. C is incorrect because the bottom right screw is the vertical adjustment screw. D is incorrect because the bottom left screw is a variable position slot. Incorrect answer. Please choose another answer.

Ultrasonic (Sonar)-based Systems Service and Diagnosis

10.	What ADAS system Detection Zone does the above pattern represent?
		a. Rear Corner Radar
		b. Ultrasonic Sensors
		c. Multifunction Forward Facing Camera
		d. Surround View Camera
As shown on page 17 of the Composite Vehicle 1, ultrasonic sensors have the illustrated patterns. The other three choices are incorrect for the image shown. Incorrect answer. Please choose another answer.