AT-115 Final Exam
A battery rated at 1000 cold cranking amps is performing poorly. The technician wants to perform a load test. How many amps should the battery be tested at?
500
A high rate or capacity discharge test was just performed on a fully charged 12 volt battery. An acceptable voltage reading would have been ____ volts. (temp. 80 degrees)
9.6 volts
ASE QUESTION: A technician is conducting a high-rate discharge (capacity) test on a 12 volt battery. With the proper load applied, the battery voltage should fall NO LESS THAN _____________?
9.6 volts after 15 seconds
What type of battery charger is recommended if a vehicle will not be driven for several weeks at a time?
float charger
Voltage regulators most commonly control what side of the field circuit?
ground side
Which ONE of the following is NOT a 'winding design' used in starter motor armatures?
hat
Which ONE of the following will NOT increase a starter motor's torque?
increase the armature's resistance
Considering the different styles of electric motors that utilizes 'field windings', which one of the following can be designed as a starter motor to produce high torque (at 0 RPM) and does not require any gear reduction?
series
Starter armatures are comprised of what type of design?
several thin iron stampings laminated together
If the metal blade in the figure vibrates, the armature is?
shorted
Considering the different styles of electric motors that utilizes 'field windings', which one of the following is more commonly used in places other than car starters, such as wiper motors?
shunt
How many cells are in a traditional automotive battery?
six
The three active chemicals in an automotive storage battery are
sponge lead, sulfuric acid, and plate grids
Which of the following components within an alternator does not rotate?
stator
Which ONE of the following is NOT a function of a car battery?
store charging system's resistance
Which of the following battery types serves as the main automotive battery source for starting the engine?
secondary battery
Battery electrolyte specific gravity should not vary more than ____ between cells:
.050
What is a typical air gap between an alternator's rotor and stator?
0.015"
Which of the following specific gravity numbers indicates a battery that is only 50% charged?
1.190
Which of the following specific gravity numbers indicates a fully charged battery?
1.265
A battery's electrolyte is being measured for its specific gravity. The electrolyte's temperature is 500F, and the hydrometer reads 1.280. Using the illustration, what should the corrected reading be?
1.268
A battery is comprised of approximately what mixture?
1/3rd sulfuric acid and 2/3rds water
A technician is using a voltmeter and is measuring across the starter's solenoid terminals M and the battery's ground terminal while the engine is cranking. Which of the following readings should a technician expect to read on the voltmeter if the starter is operating correctly?
12 V
Typical alternators have how many poles?
12 to 14
According to the textbook at what level of voltage will damage occur within an AGM?
14.5 volts
According to the textbook what level of voltage will begin to warp battery plates in a conventional automotive battery?
15.5 volts
A 100 ampere alternator requires approximately how much engine horsepower?
2 HP
Choose the correct statement regarding a starter motor that utilizes 4 brushes
2 brushes supply power & 2 brushes provide a return to ground
What is an average range of current flow through an alternator's ROTOR?
2 to 5 amperes
In a traditional automotive battery, each cell develops how many volts?
2.1 volts
An automotive starter solenoid can require how high of amperage just to energize the solenoid's windings and pull in the solenoid's plunger?
200 amps
A battery's capacity is being tested. The battery is marked with the following information: CCA = 550 Reserve Capacity (minutes) = 100 At what amperage should the technician set the carbon pile?
275
Which of the following battery types have a longer life (7 to 10 years), can be mounted in any direction, and are standard equipment in Corvettes?
AGM
A battery is using excessive water. This can be caused by:
ALL OF THESE
The condition in Figure 6-22 could be caused by:
All of these choices
A technician is using an ohmmeter to test a starter's armature. See the illustrations below. Continuity exists as shown below. What does this mean?
Bad starter armature (grounded)
"A cranking motor has an unusually high amperage draw accompanied by slow cranking speed. Technician A says that this could be caused by bad starter bushings. Technician B says that this could be caused by the armature rubbing on the pole shoes. Who is right?""
Both Technician A and Technician B
"A starter free-running test is being made on the bench with a fully charged battery (see Figure 6-31). The current draw is higher than specs and the rpm level is lower. Technician A says that this could be caused by tight bushings. Technician B says that this could be caused by worn brushes. Who is right?"
Both Technician A and Technician B
"The starter solenoid 'pumps' in and out when attempting to crank an engine. Technician A says that this could be caused by an undercharged battery. Technician B says that this could be caused by a bad solenoid. Who is right?"
Both Technician A and Technician B
Technician A states that an easy way to remember how a battery works is to know that acid (SO4) leaves the electrolyte during discharging. Technician B states that acid (SO4) is forced from the plates back into the electrolyte during charging. Who is correct?
Both Technician A and Technician B
Technician A states that electro-magnet field coils have North poles wrapped in one specific direction. Technician B states that South pole coils are wrapped in the opposite direction of the North pole coils. Who is correct?
Both Technician A and Technician B
Technician A states that plastic-type envelopes can be used in new recombinant style batteries. Technician B states that when envelopes are used they serve as a separator between the positive and negative plates. Who is correct?
Both Technician A and Technician B
"A starter motor spins but does not crank the engine. This could be the result of?"
Both a slipping drive and worn crankshaft thrust
"On the type of starter motor drive in Figure 6-21, how is the pinion gear engaged with the flywheel gear?"
By release of pinion inertia
What battery rating is tested at 32°F (0°C)?
Cranking amperes (CA)
Which style of stator winding has CURRENT FLOWING in parallel?
Delta
Which style of stator winding produces the highest amount of amperage?
Delta
Which style of stator winding requires higher RPM (meaning that it does not perform well at low RPMs)
Delta
An alternator's rotor will contain two pole pieces. Choose the ONE correct ANSWER about the pole piece.
Each pole piece will be designated as EITHER North or South pole
How does a starter convert electrical energy to mechanical energy?
Electrical current and magnetic forces cause an armature to rotate
Which ONE of the following must occur in order to conduct starter voltage drop testing?
Engine must be cranking
Which of the following is the symbol for sulfuric acid (electrolyte)?
H2SO4
There can be either an equal number of positive and negative plates or one more negative plate than positive plate
In one battery cell
"A circuit test is being made on a starting system (see Figure 6-76). While cranking, the voltmeter reads 0.4V. Technician A says to replace the starter switch; it is bad. Technician B says that the ground cable is too small to carry the current. Who is right?"
Neither Technician A nor Technician B
"An engine has an intermittent start problem. When this happens, a click is heard. Technician A says that this could be caused by a bent flywheel. Technician B says that this could be caused by too many starter shims. Who is right?"
Neither Technician A nor Technician B
A battery is being tested as pictured in Figure 6-72. Technician A says to maintain the load for 30 seconds. Technician B says to apply a load equal to the cold cranking rating of the battery. Who is right?
Neither Technician A nor Technician B
The built-in hydrometer on a sealed battery appears light yellow in color. Technician A says to load test the battery. Technician B says to charge the battery at 40A for 60 minutes. Who is right
Neither Technician A nor Technician B
With the key off, a technician is using an ohmmeter with the red lead on the starter's M terminal and the black lead on the battery's ground terminal. The meter reads 0.2 Ω. What does this mean?
Normal reading
Which unit contains a hold-in winding and a pull-in winding?
Starter solenoid
"A starter draw test is being performed. An unusually low amperage reading is indicated (accompanied by a slow cranking speed). Technician A says that a possible cause could be poor brush or commutator condition. Technician B says that a possible cause could be lack of clearance between the armature and the pole shoes. Who is right?"
Technician A
"A starter motor is damaged beyond repair. The armature windings have been thrown outward, resulting in the destruction in Figure 6-34. Technician A says that this would have been caused by the ignition switch not fully returning from START to ON position. Technician B says that this could have been caused by a loose mounted starter. Who is right?"
Technician A
A vehicle is being jump started according to the hookup in Figure 6-80. Technician A says that this hookup is for negative ground systems. Technician B says that the vehicles must touch when using this hookup. Who is right?"
Technician A
Technician A states that gear-reduction starter motors typically use less starter amperage. Technician B states that gear-reduction starter motors typically use larger diameter battery cables. Who is correct?
Technician A
As a starter begins cranking the engine, the amperage from the pull-in winding will no longer energize the pull-in winding, but instead the remaining available amperage is sent to the crank the starter. What takes place within the starter's solenoid so that the pull-in winding is no longer energized while the starter is cranking?
The "S" terminal removes voltage from the pull-in winding
A 12-V battery that has just failed a capacity test is being charged at 40A. After three minutes of charge, with the charger still operating, a voltmeter hooked across the battery reads 15.8 V. What does this indicate?
The battery is sulphated and should be replaced
"During a starter voltage drop test, the reading across the negative battery cable was recorded at 0.1V. What can be assumed?"
The cable is okay
Before you make or break connection in an electric circuit, you should?
first disconnect the battery ground cable
Which style of stator winding has CURRENT FLOWING in series?
Y
A negative-plate ground and a positive-plate group, nested together with separators between, are called?
a cell/element
The magnetic field strength of a coiled conductor is often expressed in units of?
ampere-turns
The neutral safety switch is located
between the ignition switch and the starter solenoid
Within starter motors the brushes ride upon what?
commutators
Considering the different styles of electric motors that utilizes 'field windings', which one of the following can be designed as a starter motor that produces high torque and constant speed?
compound
Which of the following answers is NOT correct regarding an alternator's "Rectifier Bridge"?
converts DC to AC
Adding plate area to a battery cell increases:
current availability
A charging system that is charging at too high of voltage will?
damage a battery
Which of the following is sometimes used in an alternator in order to direct voltage from the stator windings for the purpose of powering the alternator's FIELD?
diode trio
Which one of the following terms is used to describe an alternator diode that turns on an alternators field?
excite
A technician is attempting to use two failed alternators (one from the car and another off of the shelf) to make one good operational alternator. The car's original alternator delivered 100 amperes. After assembling the alternator, he notices that the battery charges much faster than the previous alternator (too much amperage). What most likely occurred during the rebuild process?
installed a different rotor in the new alternator
Considering late model starters, which of the following is NOT a correct statement?
late model starters that will not crank should be diagnosed by tapping on the case with a hammer
When a battery discharges _____________ _____________ is formed on the plates (both positive and negative plates).
lead sulphate
When looking at a battery's charge indicator, what does a clear dot signify?
low level of electrolyte
Which ONE of the following is NOT considered a "Sealed Lead-Acid" battery?
low-maintenance
Within an alternator, each one of the stator's windings must have a minimum of how many diodes?
one positive and one negative
When a starter's solenoid is energized and after the plunger has completely 'pulled-in' what occurs within the solenoid in terms of the winding(s)?
one solenoid plunger winding is energized
What component within a starter motor prevents damage from occurring whenever the engine starts running (at a faster speed than the starter motor is rotating)
one-way clutch
One battery plate "group" has several plates soldered together via the plate strap. The plate group contains?
only negative plates or positive plates
According to the textbook, what is the major cause of premature battery failure?
over-charging
An electric motor that is called a "shunt style" has the field windings installed in what path with the armature?
parallel
What constitutes the major difference between standard and maintenance-free batteries?
percent of alloy in the plate grids
Series-wound electric motors ________.
produce maximum power at 0 RPM
A starter motor solenoid uses two coils. They are called?
pull in and hold in
As the discharge rate of a battery is increased, the voltage of the battery will be?
reduced
All of the following are used in starter control circuits EXCEPT which ONE of the following?
reverse switch
Which of the following components is responsible for generating a magnetic field inside of an alternator?
rotor
Starters motors must have how many brushes in comparison to the number of poles?
same quantity
When measuring the battery's electrolyte specific gravity, what is the test actually measuring?
the weight of the electrolyte
Which of the following components is found within an alternator's voltage regulator circuit and is used to compensate for changes in temperature?
thermistor
An alternator produces how many phases of alternating current that must be rectified?
three
According to the basic battery principle, what is the minimum number of dissimilar metals that are required to be placed into acid which is necessary to produce electricity?
two