Question 1

The inside of both bellows boots are contaminated with power steering fluid on a rack and pinion steering gear. Technician A says if fluid is leaking past a rack seal into one boot, oil may flow through the breather tube to the opposite boot. Technician B says that there should be fluid in the bellows boot, and this is a normal condition. Who is correct?

Accepted Answer

Technician A is correct. If power steering fluid is leaking past a rack seal into one boot, it may flow through the breather tube to the opposite boot. Technician B is incorrect, as there should not be fluid in the bellows boot, and it is not a normal condition. The bellows boot is designed to protect the steering mechanism from dirt and debris, not to hold fluid.

Question 2

Technician A says when a vehicle with an electronic variable orifice (EVO) steering system is operating below 10 mph and the steering wheel rotation is above 15 rpm, power steering assist is increased. Technician B says on this vehicle, power steering assist is decreased when the vehicle speed is above 25 mph. Who is correct?

Accepted Answer

Electronic Variable Orifice (EVO) steering systems adjust the level of power steering assist based on vehicle speed and steering wheel rotation speed. At lower speeds and higher steering wheel rotation speeds, power steering assist is increased to make steering easier during maneuvers such as parking. At higher vehicle speeds, power steering assist is decreased to provide better road feel and stability. Therefore, both Technician A and Technician B are correct.

Question 3

Technician A says that on an electronically controlled four-wheel steering system, the rear wheels are steered in the same direction as the front wheels at vehicle speeds below 10 mph. Technician B says that on an electronically controlled four-wheel steering system, the rear wheels are steered in the opposite direction to the front wheels at speeds above 45 mph. Who is correct?

Accepted Answer

Technician A is correct. At speeds below 10 mph, the rear wheels are steered in the same direction as the front wheels to improve low-speed maneuverability. There is no evidence to support Technician B's claim that the rear wheels are steered in the opposite direction to the front wheels at speeds above 45 mph.

Question 4

On a power steering rack system, a customer complains that the steering wheel is not level. The concern is verified during a road test. It is also noticed that the wheel is sometimes off to the right, and sometimes off to the left. The most likely cause of this condition is:

Accepted Answer

Worn mounting bushings for the power steering rack housing can cause the steering wheel to be off-center and inconsistent, as they allow the rack to move, affecting steering alignment.

Question 5

In a power rack and pinion steering gear the breather tube:

Accepted Answer

The answer of In a power rack and pinion steering...

Question 6

Electronic power steering (EPS) operation is being discussed. Technician A says the steering sensor informs the EPS control module regarding the direction of steering wheel rotation. Technician B says the interface in the steering sensor amplifies the DC voltage signal from the steering sensor. Who is correct?

Accepted Answer

Technician A is correct because the steering sensor does indeed inform the EPS control module about the direction in which the steering wheel is being turned, which is crucial for the system to provide the appropriate amount of power assistance. Technician B is incorrect because it is not the function of the interface in the steering sensor to amplify the DC voltage signal; the signal conditioning and amplification, if needed, are typically handled by the EPS control module or a dedicated signal processing unit, not the steering sensor itself.

Question 7

Inputs in the electronic variable orifice (EVO) steering system include the:

Accepted Answer

The EVO steering system uses the vehicle speed sensor as an input to adjust the amount of power steering assist provided, so D is the correct answer. The throttle position sensor, coolant temperature sensor, and intake air temperature sensor are not typically used as inputs for this system.

Question 8

Technician A says when backing up a trailer, a four-wheel steering system on the tow vehicle provides better trailer response to vehicle steering inputs. Technician B says when towing a trailer, a four-wheel steering system on the tow vehicle reduces the articulation angle between the tow vehicle and the trailer during lane changes. Who is correct?

Accepted Answer

Both technicians are correct. A four-wheel steering system on the tow vehicle can indeed provide better trailer response to vehicle steering inputs while backing up and reduce the articulation angle between the tow vehicle and trailer during lane changes.

Question 9

An electronic power steering (EPS) system is being discussed. Technician A says if the engine stalls and the ignition switch is on, the EPS remains operational. Technician B says if the steering wheel is turned and held fully in one direction, the power module reduces current flow through the steering gear motor to prevent motor overheating. Who is correct?

Accepted Answer

Technician A is correct as EPS systems use electric power to assist with steering, so even if the engine stalls, the EPS system will still have power from the battery. 
Technician B is correct as in order to prevent overheating of the steering gear motor, the power module may reduce current flow when the steering wheel is turned and held fully in one direction. Therefore, both technicians are correct.

Question 10

A technician notices during a road test for a pulling complaint that the steering wheel is slow to return to center and requires higher than normal steering effort. The most likely cause of this condition could be:

Accepted Answer

An over-adjusted steering rack preload can cause the steering wheel to be slow to return to center and require higher than normal steering effort because it increases the friction and resistance within the steering mechanism.

Question 11

The power steering pump belt breaks on a rack and pinion power steering system. Under this condition:

Accepted Answer

If the power steering pump belt breaks, the steering system reverts to a manual system, making steering effort higher. The spool valve inside the rotary valve will still move when the steering wheel is turned, but without the assistance of the power steering pump, it will not have any effect on the steering. Power steering fluid may still be forced from the rack seals due to pressure from turning the steering wheel, but this is not directly related to the broken belt. The torsion bar is not affected by a broken power steering pump belt.

Question 12

Technician A says the steering system's ability to isolate road shock from the steering wheel is reduced when the number of friction points is reduced. Technician B says a steering system has increased road feel when the number of friction points is reduced. Who is correct?

Accepted Answer

Technician A is correct because reducing the number of friction points in a steering system can lead to less isolation of road shock, making vibrations and bumps more noticeable to the driver. Technician B is also correct because reducing friction points can enhance the road feel, providing the driver with a more direct and responsive steering experience.

Question 13

What are the two input sensors in an electronic variable orifice (EVO) steering system?

Accepted Answer

The answer of What are the two input sensors in...

Question 14

If an electrical defect occurs in a 4WS system the:

Accepted Answer

If an electrical defect occurs in a 4WS system, the rear wheels will remain in the centered position. There will be no steering control of the rear wheels, positive or negative phase.

Question 15

In a center take-off power rack and pinion steering gear, the tie rods are attached to:

Accepted Answer

The answer of In a center take-off power rack and...

Question 16

The component in a rack and pinion steering gear that compares to the center link in a parallelogram steering linkage is the:

Accepted Answer

The rack in a rack and pinion steering gear is the component that moves back and forth, similar to the center link in a parallelogram steering linkage. The pinion is the gear that meshes with the rack to convert the rotational motion of the steering wheel into linear motion of the wheels. The inner and outer tie-rod ends are connected to the ends of the rack and help transfer the motion to the steering knuckles. However, they do not perform the same function as the center link in a parallelogram steering linkage.

Question 17

Hybrid vehicles are equipped with electronic power steering for all of the following reasons EXCEPT:

Accepted Answer

The statement "there is no room for conventional power steering" is not a valid reason for hybrid vehicles being equipped with electronic power steering. Other reasons listed, such as fuel efficiency and maintaining power steering functionality during engine idling, are valid reasons for the use of electronic power steering in hybrid vehicles.

Question 18

Power rack and pinion steering gear operation are being discussed. Technician A says the position of the rotary valve inside the spool valve directs the fluid to the appropriate side of the rack piston. Technician B says during a right turn, fluid is directed to the right side of the rack piston and the rack is moved to the left. Who is correct?

Accepted Answer

Both technicians are correct. The rotary valve inside the spool valve directs the fluid to the appropriate side of the rack piston based on the steering input, and during a right turn, fluid is directed to the right side of the rack piston, moving the rack to the left.

Question 19

On a four-wheel steering (4WS) system, all of the following statements are true EXCEPT:

Accepted Answer

A 4WS system primarily enhances maneuverability and stability, but it does not directly reduce tire wear.

Question 20

Where is the actuator solenoid mounted in an electronic variable orifice (EVO) steering system?

Accepted Answer

The answer of Where is the actuator solenoid mounted in...

Quiz 13: Rack and Pinion Steering Gears and Four Wheel Steering