Exam Review Flashcards
(145 cards)
1
Q
A Live axle leaf-spring suspension provides excellent ___ stability
A
Lateral
2
Q
Define Live Axle rear suspension
A
one where the diferential, axle housing, wheel bearings, brakes act as a unit
3
Q
During Breaking and Deceleration the front of the differential is twiested_____
A
Clockwise
4
Q
axle tramp occurs during hard ____
A
acceleration
5
Q
in many live axle coil spring rear suspensions, the differential torque is absorbed by the trailing lower ______
A
control arm
6
Q
In a modified macpherson strut the coil spring seat is located on ______
A
stamped lower control arm
7
Q
in some multi link rear suspension systems, the rubber mounting busings between the suspension member and the chasis are _____ in the fore and aft dierection and _____ in the lateral directio
A
Soft and Stiff
8
Q
A fiberglass mono-leaf rear spring is compact, light weight and ______ free
A
corrosion
9
Q
when the rear springs are sagged the caster angle on the front suspension becomes more_______
A
positive
10
Q
in the double _____ rear suspension system, the control arm design and pivot locations on the rear toe control are provide____ change in toe-in during wheel jounce
A
Wishbone
Minimal
11
Q
Rear Axel tramp is caused by:
A irregular roads
B Bent rear control arm
C Engine torque transmitted through the drive shaft
D Improper rear wheel alignment
A
C Engine Torque transmitted through the drive shaft
12
Q
All of these statements about a live axel leaf spring rear suspension are true EXCEPT
A during acceleartion the front of the differential twists upward
B the differential toque in a live axle rear suspension is applied to the springs
C while decelerating and braking, the front of the differential twists downward
D this type of rear suspension has a small amount of unsprung weight
A
D - small unsprung weight
13
Q
Rear Axel tramp occurs during
A Hard acceleration
B Deceleration
C high-speed driving
D cornering at high speed
A
A Hard Acceleration
14
Q
In a semi independent rear suspension system, some individual wheel movement is provided by
A the u section channel and integral stabilizer bar
B the struts
C the Trailing Arms
D Track bar and brace
A
A U Section channel and integral stabilizer bar
15
Q
IN a semi independent rear suspension system
A the track bar and brace absorb differential toque
B the trailing arms prevent lateral wheel movement
C the lower coil springs seats may be on the trailing arms
D the lower end of the shock absorbers may be attached to the track bar
A
C the lower coild spring seats may be on the trailing arms
16
Q
All of theese statemtns about Modified Marpherson are true except
A the lower control arms prevent lateral wheel movement
B the tie rods control for-and aft wheel movement
C the strut is bolted to the lower end of the spindle
D the upper strut mount is retained on the top of the strut
A
B the tie rods control fore-and-aft wheel movement
17
Q
IN an independent rear suspension with a lower control arm and ball joint:
A the ball joint is pressed into the tie rod
B the strut is bolted to the top of the knuckle
C the lower coil spring seat is moutned on the streut
D the suspension adjustement link is connected from the lower control arm to the chassis
A
B the strut is bolted to the top of the knuckle
18
Q
Sagged rear springs may cause:
A slow steering wheel return after turning a croner
B decreaded steering effort
C decreased posistive caster on the front wheels
D harsh ride quality
A
A Slow steeering wheel return after tunring a corner
19
Q
The adjustment link in a multilink rear suspension:
A provides a rear wheel caster adjustment
B provides a rear wheel toe adjustment
C reduces fore-and-aft rear wheel movement
D absorbs engine torque transmitted through the drive shaft
A
B Provides a rear wheel toe adjustment
20
Q
- In some collapsible steering columns, ______ in the outer column jacket and steering shaft shear off if the driver is thrown against the steering wheel in a frontal collision.
A
PLastic Pins
21
Q
The driver’s side air bag protects the driver if the vehicle is involved in a ______collision above a specific speed.
A
Frontal
22
Q
3. In an air bag system, a \_\_\_\_\_\_ in the steering column maintains positive electrical contact between the air bag module and the air bag electrical system as the steering wheel is rotated.
A
Clock Spring
23
Q
- In a parallelogram steering linkage, the center link connects the pitman arm to the ______
A
Steering Gear
24
Q
- In a parallelogram steering linkage, the pitman arm and the ______ position the center link and tie rods at the correct height.
A
Idler Arm
25
6. In a wear-type pitman arm, a ______is positioned in the outer end of the pitman arm.
Ball socket
26
7. In a parallelogram steering linkage, the tie rods are parallel to the _____
Lower Control Arms
27
8. The clamp opening in a tie rod sleeve must be positioned away from the_____ in the tie rod sleeve.
SLot
28
9. In a rack and pinion steering system, the rack is connected directly to the _______
Pinion gear and steering column
29
10. Compared with a parallelogram steering linkage, a rack and pinion steering linkage has a reduced number of _____ points.
Friction
30
1. A typical air bag deployment time is: A. 1.5 minutes.
B. 1 minute.
C. 30 seconds.
D. 40 milliseconds.
D 40 Milliseconds
31
2. Many collapsible steering columns have:
A. Plastic pins in the two-piece outer jacket.
B. A collapsible bellows in the two-piece outer jacket.
C. Steel pins in the two-piece lower steering shaft.
D. A rubber spacer in the two-piece lower steering shaft.
A. Plastic pins in the two-piece outer jacket.
32
3. The clock spring electrical connector:
A. Maintains electrical contact between the air bag inflator module and the air bag electrical system.
B. Is mounted above the steering wheel.
C. Contains three spring-loaded copper contacts.
D. Provides electrical contact between the signal light switch and the signal lights.
A. Maintains electrical contact between the air bag inflator module and the air bag electrical system.
33
4. An active steering column has all of these components EXCEPT:
A. A pyrotechnic actuator.
B. A section of energy-absorbing steel.
C. A telescoping cylinder.
D. A pull-out pin that allows easier column collapse.
C. A telescoping cylinder.
34
5. All of these statements about rack and pinion steering linkages are true EXCEPT:
A. The tie rods are parallel to the lower control arms.
B. The tie rod position depends on the steering gear mounting.
C. The tie rods are connected to the pinion in the steering gear.
D. The outer tie rod ends connect the tie rods to the steering arms.
C. The tie rods are connected to the pinion in the steering gear.
35
6. All these statements about parallelogram steering linkages are true EXCEPT:
A. Tie rod sleeves have the same type of thread in both ends of the sleeve.
B. Loose steering linkages may cause excessive tire tread wear.
C. Loose steering linkage causes excessive steering wheel free play.
D. The pitman arm helps maintain the proper center link and tie rod height.
A. Tie rod sleeves have the same type of thread in both ends of the sleeve.
36
7. While discussing idler arms:
A. Some idler arms contain a tapered roller bearing.
B. The idler arm bracket is bolted to the upper control arm.
C. A worn idler arm has no effect on front wheel toe.
D. A partially seized idler arm bearing increases steering effort.
D. A partially seized idler arm bearing increases steering effort.
37
8. In a parallelogram steering linkage, the tie rods are parallel to the lower control arms to:
A. Improve ride quality.
B. Provide longer steering linkage life.
C. Extend shock absorber and spring life.
D. Reduce toe change during upward and downward front wheel movement.
D. Reduce toe change during upward and downward front wheel movement.
38
9. A rack and pinion steering gear:
A. Has tie rods that connect the rack directly to the steering arms.
B. May be bolted to the vehicle frame.
C. Has inner tie rod ends that are pressed onto the rack.
D. Has more friction points compared with a parallelogram steering linkage.
A. Has tie rods that connect the rack directly to the steering arms.
39
10. While discussing steering linkages and dampers:
A. In a rack and pinion steering gear, the rack positions the tie rods parallel to the lower control arms.
B. A rack and pinion steering gear is used on most rear-wheel-drive cars.
C. A steering damper is used on many front-wheel-drive vehicles.
D. A defective steering damper may cause excessive steering effort.
D. A defective steering damper may cause excessive steering effort.
40
1. Explain how a collapsible steering column protects the driver in a frontal collision.
it collapses away from the driver reducing injury as the driver hits the column
41
2. Explain how the driver’s side air bag protects the driver in a frontal collision.
inflated air bag prevents driver from hitting wheel, whindsheild or panel
42
3. Describe the purpose of a clock spring.
MAintains posistive electrical contact between inflator module and air bag system
43
4. List the switches commonly found in a steering column.
turn signal, ignition, dimmer switch
44
5. Describe the type of mechanism used to lock the steering wheel and gear shift when the ignition is in the Lock position.
a lock plate is used and a lever engagees it to clock the steering wheel
45
6. Describe the pivot points in the upper shaft and upper column tube in a tilt steering wheel.
pivots on two bolts and universal joint
46
7. List the wear points in a parallelogram steering linkage.
tie rods, sockets and ends
idler arm
center link end
47
8. List the five main components in a parallelogram steering linkage, and explain the purpose of each component.
pitman arm - connects center link to steering gear,
center link - connects pitman arm to tie rods, idlear arm assembly - supports right side of center link,
tie rods inner - conects center link to outer tie rod,
outer tie rods - connect tie rod to steering arms
48
9. Describe the basic design of a rack and pinion steering linkage.
the rack rod with teeth on one side. slides horizontally due to pinion gear connected to steering column, has inner and outer tie rods
49
10. Explain the advantages of a rack and pinion steering linkage compared with a parallelogram steering linkage.
Less number of friction points and is light and compact
50
1. Explain why four-wheel alignment is essential on cars with semi-independent or independent rear suspension.
more likely to experience rear wheel allignment problems
51
2. Explain why the rear wheel toe angle, thrust angle, and camber should be correct before adjusting the front suspension
angles.
Dog tracking may/will occur
52
3. Describe the term total toe and what the difference is between a positive toe angle and a negative toe angle.
total toe is difference in distance between front of tires and rear distance of the same tires. Positive toe is toe in and is less distance at front of tire, negative toe is toe out meaning more distance at front
53
4. Explain what will happen if toe angles are outside the allowed tolerance.
Will cause feathered tire wear, 1/8 of an in toe in error is equivalent to dragging the tires crosswise 11 feat for every mile driven
54
5. Explain why excessive positive camber wears the outside edge of the tire tread.
the tire is tilting inward at the bottom causing more wear on that corner
55
6. Describe the type of tire tread wear caused by an improper toe setting
causes rapid feathered tire wear
56
7. Explain why positive caster provides increased directional stability.
causes larger tire contatc area behind pivot point. This contact area tends to follow the pivot point returning wheels to straight ahead position
57
9. Explain why positive caster causes harsh riding quality.
may be because the caster line is actually aimed at road irregularities
58
10. Define toe-in and toe-out.
toe-in when front distance of tires is less than rear distance
toe- out - front distance is more than rear distance
59
1. Excessive toe-out on the right rear wheel moves the thrust line to the _____ of the geometric centerline.
Right
60
2. If the thrust line is positioned to the left of the geometric centerline so the thrust angle is more than specified, the
steering pulls to the _____
right
61
3. Directional stability refers to the tendency of a vehicle to travel straight ahead without being _____
Steered
62
4. When the front wheel camber is negative, the centerline of the tire and wheel is tilted_____ in relation to the true vertical centerline of the tire and wheel.
inward
63
5. Excessively ______ camber on a front wheel assembly will cause the tire to wear on the inside edge.
NEgative
64
6. Negative front wheel caster decreases _____ ______ and steering wheel ____ _____.
Directional Stability
| Pulls Away
65
7. Raising the rear suspension height above the manufacturer’s specification may change the front wheel caster from _______to_____ .
Positive to Negative
66
8. Front wheel shimmy may be caused by excessive _____ caster.
Positive
67
9. Front wheel caster becomes more positive if the rear suspension height is .______
lowered
68
10. If the front suspension height is lowered on a MacPherson strut suspension, the front wheel caster becomes______
less positive
69
1. While diagnosing front wheel toe problems:
A. The front wheels are set to a straight-ahead position on most front-wheel-drive cars.
B. Driving forces tend to move the front wheels toward a toe-in position on a rear-wheel-drive car.
C. Improper toe adjustment may cause feathered wear on the front tire treads.
D. Sagged front springs may increase the front wheel toe-out on a short-and-long arm suspension system.
C. Improper toe adjustment may cause feathered wear on the front tire treads.
70
2. “Feathering” type wear of a rear tire is likely caused
by:
A. Improper rear wheel camber alignment.
B. Improper rear tire inflation.
C. Improper rear wheel balance.
D. Improper rear wheel toe alignment.
D. Improper rear wheel toe alignment.
71
3. A front-wheel-drive vehicle with an independent rear suspension pulls to the right when driving straight ahead. All the front suspension alignment angles are within specifications. The most likely cause of this problem is:
A. Excessive toe-out on the right rear wheel.
B. Excessive negative camber on the right rear wheel. C. Excessive toe-out on the left rear wheel.
D. Excessive positive camber on the left rear wheel.
A. Excessive toe-out on the right rear wheel.
72
4. All of these statements about the vehicle thrust line and steering pull are true EXCEPT:
A. Excessive toe-out on the left rear wheel moves the thrust line to the left of the vehicle centerline.
B. Excessive toe-in on the right rear wheel moves the thrust line to the right of the vehicle centerline.
C. If the thrust line is moved to the left of the vehicle centerline, the steering tends to pull to the right.
D. Excessive toe-out on the right rear wheel causes the steering to pull to the left.
B. Excessive toe-in on the right rear wheel moves the thrust line to the right of the vehicle centerline.
73
5. While diagnosing suspension and wheel alignment problems:
A. Road crown has no effect on vehicle steering or wheel alignment.
B. Vehicle loads have no effect on wheel alignment.
C. Steering angles are designed to reduce tire wear and provide directional control.
D. Wheel alignment angles do not affect riding quality.
C. Steering angles are designed to reduce tire wear and provide directional control.
74
6. While diagnosing the vehicle geometric centerline and thrust line:
A. The front and rear wheels should be parallel to the geometric centerline.
B. The thrust angle is the difference between the front wheel camber and steering axis inclination (SAI) angles.
C. If the thrust angle is more than specified, front wheel shimmy may occur.
D. A bent front cradle may cause the thrust angle to be more than specified.
A. The front and rear wheels should be parallel to the geometric centerline.
75
7. While driving straight ahead, a front-wheel-drive car pulls to the right. The most likely cause of this problem is:
A. More positive camber on the left front wheel compared to the right front wheel.
B. Sagged front springs and improper front wheel toe setting.
C. Less positive caster on the right front wheel compared to the left front wheel.
D. The SAI on the right front wheel is 1.5 degree more than the SAI on the left front wheel.
B. Sagged front springs and improper front wheel toe setting.
76
8. While adjusting front wheel camber and diagnosing camber-related problems:
A. During front wheel jounce travel, the positive camber increases.
B. Excessive positive camber on a front wheel causes premature wear on the inside edge of the tire tread.
C. If the right front wheel camber is 1.5 degrees and the left front camber is 0.5 degree, the steering pulls to the left.
D. Excessive positive camber on both front wheels may cause front wheel shimmy.
A. During front wheel jounce travel, the positive camber increases.
77
9. A driver complains of harsh riding and the suspension height is normal. The most likely cause of this problem is:
A. Excessive negative camber on both front wheels.
B. Excessive positive caster on both front wheels.
C. The left front wheel has more positive caster than the right front wheel.
D. Both front wheels have negative camber and negative caster.
B. Excessive positive caster on both front wheels.
78
10. Excessive positive caster may cause all of these problems EXCEPT:
A. Front wheel shimmy.
B. Harsh ride quality.
C. Excessive steering effort. D. Slow steering wheel return.
D. Slow steering wheel return.
79
1. Define steering axis inclination (SAI).
SAI - inward tilt of line through center of the upper strut mount and lower ball joint to the true vertical centerline
80
2. Explain the included angle.
included angle is the sum of the SAI angle and camber angle
81
3. Explain how SAI helps to return the steering wheel to the center position after a turn.
The chassis lifts during a turn then when released it lowers and SAI helps wheels return to straight-ahead position
82
4. Define negative scrub radius and positive scrub radius, including the type of suspension system on which each
condition is used.
Negative scrub radius is the SAI line meets the surface outside the tire centerline
Positive scrub is the SAI line meets the surface inside the tire center line - conventional short long arm,
83
5. Describe front wheel setback.
condidtion where one wheel is moved rearward and is usually casued in front wheels due to collisions
84
6. Explain the necessary wheel position to provide proper tracking.
each front wheel and each rear wheel must be at an equal distance from the vehicle centerline
85
7. Describe the necessary axle position to provide correct wheelbase.
axle must be at 90° angle to the vehicle centerline
86
8. Explain the turning angle of each front wheel during a turn.
the inside wheel has a sharper angle than the outside wheel when turning
87
9. Explain the effects of front wheel setback.
cause steering to pull to one side, where one wheel is moved rearward
88
10. Describe the effects of rear axle offset.
causes steering to pull to one side
89
1. A 3-degree difference in the SAI angle on each side of the front suspension may cause_____ during hard breaking
Steer Pull
90
2. A 3-degree difference in the SAI angle on each side of the front suspension may cause increased______ during hard
acceleration.
Torque Steer
91
3. When a front suspension has a positive scrub radius, the SAI line meets the road surface _____ the true vertical centerline of the tire.
Inside
92
4. A negative scrub radius tends to turn the front wheels _____when the car is driven.
inward
93
5. Most rear-wheel-drive cars have a ______scrub radius.
Positive
94
6. Wheelbase is the distance between the front and rear wheel ___
Centers
95
7. Directional stability is the tendency of a vehicle to remain in the _____position when driven straight ahead on a level road
straight ahead
96
8. During a turn, the _____front wheel turns at a sharper angle.
inside
97
9. Tracking refers to the _______relationship between the front and rear wheels.
Alignment
98
10. During a turn, centrifugal force causes all the tires to slip a certain amount, and the actual center of the turn is shifted
______of the theoretical center of the turn.
Ahead
99
1. When measuring front wheel alignment angles, to calculate the included angle on the left front wheel when the camber on this wheel is positive:
A. Add the camber to the toe setting.
B. Add the camber to the SAI angle.
C. Add the SAI to the caster angle.
D. Subtract the SAI from the toe setting.
B. Add the camber to the SAI angle.
100
2. While diagnosing problems related to scrub radius:
A. If the SAI line contacts the road surface inside the vertical tire and wheel centerline, the scrub radius is negative.
B. Front-wheel-drive cars usually have a negative scrub radius and driving forces move the front wheels outward.
C. If the SAI line contacts the road surface outside the tire and wheel vertical centerline, driving forces turn the front wheels outward.
D. Larger-than-specified front tires may change the scrub radius from positive to negative.
D. Larger-than-specified front tires may change the scrub radius from positive to negative.
101
3. While diagnosing a diamond-frame condition and frame twist:
A. A diamond-frame condition causes the wheelbase to be unequal on the two sides of the vehicle.
B. A diamond-frame condition does not affect steering pull and directional stability.
C. Frame twist is usually caused when a vehicle is involved in a side collision.
D. When frame twist occurs, the front or rear chassis does not sit level in relation to the road surface.
D. When frame twist occurs, the front or rear chassis does not sit level in relation to the road surface.
102
4. While diagnosing and adjusting turning radius:
A. When a vehicle is making a left turn, the left front wheel turns at a sharper angle than the right front wheel.
B. Improper turning radius may be caused by a bent tie rod on a short-and-long arm suspension system.
C. Improper turning radius may be caused by an improperly positioned rack-and-pinion steering gear on a front- wheel-drive car.
D. Improper turning radius is adjusted by turning an eccentric strut-to-steering knuckle bolt.
A. When a vehicle is making a left turn, the left front wheel turns at a sharper angle than the right front wheel.
103
5. All of these statements about unitized body design are true EXCEPT:
A. The frame and body are combined as one unit.
B. The external frame assembly is eliminated.
C. Some body members such as quarter panels do not contribute to body strength and rigidity.
D. Body strength is obtained by body shape and design.
C. Some body members such as quarter panels do not contribute to body strength and rigidity.
104
6. A front-wheel-drive car has an improper toe-out on turns setting, and a visual check indicates all the steering linkage and suspension components are satisfactory. The most likely cause of this problem is:
A. A bent lower control arm.
B. A bent front strut.
C. A front strut tower that is out of position.
D. A bent steering arm.
C. A front strut tower that is out of position.
105
7. All of these statements about SAI and front spindle movement are true EXCEPT:
A. When the steering wheel is turned, the front spindle movement is parallel to the road surface.
B. When the SAI angle is increased, the steering wheel returning force is increased.
C. The SAI angle tends to maintain the wheels in a straight-ahead position.
D. Greater SAI angle is necessary on front-wheel-drive cars to provide directional stability.
A. When the steering wheel is turned, the front spindle movement is parallel to the road surface.
106
. Front wheel setback occurs when one front wheel is:
A. Tilted inward from the true vertical position.
B. Moved rearward in relation to the opposite front wheel.
C. Tilted rearward from the true vertical position.
D. Inward from its original position.
B. Moved rearward in relation to the opposite front wheel.
107
9. A light-duty truck with a one-piece rear axle housing and a leaf-spring rear suspension has excessive toe-out on the left rear wheel and too much toe-in on the right rear wheel. The most likely cause of this problem is:
A. A broken center bolt in the left rear spring.
B. Both rear springs are sagged.
C. A bent rear axle housing.
D. Worn-out rubber bushings in the shock absorbers.
A. A broken center bolt in the left rear spring.
108
10. While discussing scrub radius:
A. Most front-wheel-drive cars have a positive scrub radius.
B. If the SAI line meets the road surface outside the tire vertical centerline, the scrub radius is positive.
C. Scrub radius is adjusted by shifting the upper strut tower on a MacPherson strut front suspension.
D. Incorrect scrub radius may be caused by larger-than-specified front tires.
D. Incorrect scrub radius may be caused by larger-than-specified front tires.
109
1. Describe the operation of the steering sensor in a programmed ride control (PRC) system.
Mounted to steering column, sensor containts LEDs and photo diodes, a slotted disc attached to the steering shaft rotates between LED and diodes when the steering wheel is turned. Sends signal to the control module
110
2. Describe the purpose of the vehicle speed sensor signal in a programmed ride control (PRC) system.
sensor sends a vehicle speed signal to the control module
111
3. Explain how air is forced into an air spring in a rear load-leveling air suspension system.
Rear height sensors signals the suspension control module to raise the rear suspension. Air springs are inflated into the springs to raise or lower the system through an electric solenoid type valve
112
4. Describe the action taken by the control module if the control module in an electronic air suspension system receives a lower vehicle command from a rear suspension sensor with the doors closed, the brake pedal released, and the vehicle traveling at 60 mph (100 km/
all commands are serviced by a 45-second averaging method to prevent excessive suspension height correctios
113
5. Describe the action taken by the control module if the engine is running with a door open, and the control module receives a lower vehicle command from the height sensor in a rear load-leveling air suspension system.
lower vehicle commands are supressed until doors are closed to prevent hitting curbs
114
6. List the conditions when the On/Off switch in an electronic air suspension system must be turned off.
Before vehicle is hoisted, jacked, or towed
115
```
7. Describe the conditions required for the control module to turn on the suspension warning lamp continually with the
engine running in an electronic air suspension system.
```
When the control module senses a system defect it will contiunally light the warning light with the engine running
116
8. Explain why the control module in an electronic air suspension system services all commands by a 45-second averaging method when the doors are closed and the brake pedal is released.
to prevent excessive suspension height corrections on irregular road surfaces
117
1. The armature response time is_____ milliseconds in a programmed ride control (PRC) system strut.
1-12
118
2. In a programmed ride control (PRC) system, if the car is accelerating with the throttle wide open, the PRC system is in
the ______ mode.
Firm
119
```
3. When the programmed ride control (PRC) mode switch is in the Auto position, the control module changes to the firm mode if lateral acceleration exceeds .
______
```
0.35 g (gravity)
120
4. In a programmed ride control (PRC) system, lateral vehicle acceleration is sensed from the _____sensor.
Speed
121
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5. In a rear load-leveling air suspension system, the control module energizes the compressor relay when a ______
command is received.
```
Raise
122
Two height sensors are mounted on ______the suspension in an electronic air suspension system.
Front
123
In an electronic air suspension system two hours after the ignition switch is turned off, completed, but ______commands are ignored.
Raise
124
8. In a rear load-leveling air suspension system, if the On/Off switch in the trunk is off, the system is _____
Off
125
An electronic rotary height sensor contains a _____ _____
Magnet Slide
126
```
10. In a continuously variable road sensing suspension system, the module senses vehicle lift and dive from some of the ____ _____
inputs.
```
Position Sensor
127
1. While discussing a programmed ride control (PRC) system:
A. The brake system pressure must be 300 psi (2068 kPa) before this mode change occurs.
B. A PRC system switches from the auto mode to firm mode if the vehicle accelerates with 90 percent throttle opening.
C. The PRC system switches to the firm mode if lateral acceleration exceeds 0.25 g.
D. The mode indicator light in the tachometer is illuminated in the plush ride mode.
B. A PRC system switches from the auto mode to firm mode if the vehicle accelerates with 90 percent throttle opening.
128
2. To increase the rear trim height in an electronic air suspension system, the control module:
A. Starts the compressor and opens the vent valve.
B. Starts the compressor and closes the rear air spring valves.
C. Stops the compressor and opens the rear air spring valves.
D. Starts the compressor and opens the rear air spring valves.
D. Starts the compressor and opens the rear air spring valves.
129
3. All these statements about air springs, shock absorbers, and struts are true EXCEPT:
A. Air springs can be mounted separately from the shock absorbers.
B. Air springs can be mounted over the front and rear struts.
C. Some struts contain a solenoid actuator that controls strut firmness.
D. Some air suspension systems have seven driver selectable operating modes.
D. Some air suspension systems have seven driver selectable operating modes.
130
```
The magneto-rheological fluid in the shock absorbers or struts in an ESC system contains:
A. Automatic transmission fluid.
B. Suspended iron particles.
C. Power steering fluid.
D. 5W-30 engine oil.
```
B. Suspended iron particles.
131
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5. To sense the distance to the vehicle in front, an adaptive cruise control system uses:
A. A video camera.
B. A short-range radar signal.
C. A digital camera.
D. A long-range radar signal.
```
D. A long-range radar signal.
132
```
6. In an ESC system with magneto-rheological fluid in the shock absorbers or struts, the control module can vary the shock absorber firmness in:
A. 1 millisecond.
B. 5 milliseconds.
C. 10 milliseconds.
D. 152 milliseconds.
```
A. 1 millisecond.
133
7. All of these statements about network systems are true EXCEPT:
A. A network system can be a single-wire or dual-wire system.
B. Some network systems operate between 0 V and 12 V.
C. Some vehicles have two network systems.
D. A fiber-optic network system has a very high data transmission rate.
B. Some network systems operate between 0 V and 12 V.
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8. In some traction control systems if the control module senses drive wheel spin, the first action taken by the control module is to:
A. Retard the spark advance and shut off the fuel injectors.
B. Apply the brakes on both non-drive wheels.
C. Apply the brake on the spinning drive wheel.
D. Apply the brake on the non-spinning drive wheel.
A. Retard the spark advance and shut off the fuel injectors.
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9. On a vehicle with a stability control system, if icy road conditions cause the vehicle to begin swerving sideways, the stability control module:
A. Applies the brakes on both rear wheels.
B. Applies the brakes on both front wheels.
C. Applies the brake on one front wheel.
D. Applies the brake on one front wheel and the opposite rear wheel.
C. Applies the brake on one front wheel.
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10. All of these statements about a rear load-leveling suspension system are true EXCEPT:
A. The On/Off switch is mounted in the vehicle trunk.
B. The control module operates the compressor relay.
C. If a door is open, the control module completes the lower suspension height commands.
D. The rear suspension has one, non-serviceable suspension height sensor.
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C. If a door is open, the control module completes the lower suspension height commands.
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2. Explain the disadvantages of a live axle leaf-spring rear suspension.
Have alot of unsprung weight and require alot of space
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3. Describe the purpose of a leaf-spring shackle.
Shackle provides fore-and-aft movement with variations in spring length
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4. Explain the differential torque action during acceleration, and describe how this torque is absorbed in a live axle coil
spring rear suspension.
Differential tends to twist differential housing and the springs. The torque is absorbed by the lower trailing arms
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5. Define axle tramp.
FWD cars lose traction with the road, causing wheels to bounce/vibrate vertically
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6. Describe the purpose of a tracking bar.
Prevents lateral Chasis Movement
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7. Explain the difference between a semi-independent and an independent rear suspension system.
Semi - Allows some individual rear wheel movement when one wheel strikes a bump
Independant - Allows individual rear wheel movement when one wheel strikes the road
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8. Explain the advantages of an independent rear suspension compared with a live axle rear suspension.
Better Ride quality, traction, and decreased tire wear when compared to live-axel
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9. Describe the advantage of mounting the differential to the chassis in a rear-wheel-drive car with an independent rear suspension.
Reduces unsprung weight, improving ride quality
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10. Describe the components that position the upper end of the knuckle in a multilink rear suspension.
Bushing and ball joint large insulating bushings
