Terms for electrical final
As a rule of thumb, for a typical non-PCM-controlled 12-volt charging system, the regulated alternator output voltage should be between_______ volts
Answer: 13.8 and 14.4
The rotating electromagnet is called the
rotor
WHen using non-powered test light o check for power, the clip should be attached to:
Answer:a known good ground
A blown fuse typically has a battery voltage on one side of the fuse and _______ volts on the other side
Answer: 0
Most DMMs can measure MIlliamps or________ directly through the meter
Answer: 10 to 20 amps
In some cases, it may be possible to use a ______ memory minder or memory saver to maintain the vehicle s memory while the vehicles battery is disconnected
Answer: 9-volt
The motor effect is greatest when the current-carrying conductor and the stationary magnetic field are at
Answer: 90 degrees
Basic DMM Measure
Answer: All of the above
The solenoid plunger movement allows a very large current flow from the battery to the starter motor____________
Answer: All of the above
______ are available in various ratings, types ,a nd sizes and must always be replaced with the same rating and type
Answer: All of the above
Where should you place the voltmeter leads when measuring the voltage drop on the ground side of the alternator
Answer: Black probe on the negative battery terminal and red probe on the case of the alternator
Battery terminals are usually _________ onto the battery cables to ensure strong, low resistance connections
Answer: Both A and B
Each starer test devise will operate slightly differently, but all should have
Answer: Both A and B
Once the cranking circuit is completed, current flows from the battery to the
Answer: Both A and B
Tech A Says that the stater solenoid switched the high current on and off Tech B says that the solenoid on the starter motor engages the starter drive with the ring gear
Answer: Both A and B
Two technicians are discussing alternators
Answer: Both A and B
Two technicians are discussing the starter control circuit
Answer: Both A and B
Two techs are discussing a starter draw test
Answer: Both A and B
When reading a DMM you have a reading of 2168 mV
Answer: Both A and B
Tech A says that excessive voltage drops reduce current flow in the starter circuit Tech B says that locating voltage drops can be done by pacing the voltmeter leads systematically in the stater circuit to narrow down the circuit to the actual fault
Answer: Both Tech A and B
Reversing the direction of current flow in the conductor will
Answer: Cause the conductor to move in the opposite direction
If voltage decreases and the resistance stays the same, then amperage will
Answer: Decrease
As the starter motor and engine cranking seed increase, the current draw_______ and quickly ________ ance the engine reaches full cranking speed.
Answer: Decreases stabilizes
The___________ Allow current to flow one way in the rectifier assembly
Answer: Diodes
A relatively small current flows through a ______ to a starter relay that controls a larger current to operate the starter solenoid, which is typically mounted atop the starter motor.
Answer: Either A or B
It is important to remember that the sum of the voltage drops across individual resistors in a series circuit is ______ the supply voltage.
Answer: Equal to
___________ of the brushes are connected directly to the end fram and ground the armature windings via the engine block to the negative battery terminal
Answer: Half
If voltage stays the same but resistance decreases, amperage must
Answer: Increase
It is important to understand that ohms law tells us that flow is ____ to resistance
Answer: Inversely proportional
It is important to understand that current ______ in all parts of a properly working series circuit
Answer: Is the same
What causes the charging system warning lamp to go out when the engine starts up
Answer: It turns off because voltage is applied to both sides of the lamp
A starter motor armature has a____ number of conductor loops ad therefore _______ segments on the commutator
Answer: Large;many
The _____ resistance fault causes an abnormally ________ current flow in the circuit and may cause the circuit protection devices, such as fuses or circuit breakers, to______ the circuit
Answer: Low; high; open
Tanks to solid state electronics and circuitry, alternators have taken over due to their superior operating characteristics, including the following except
Answer: Lower RPM
A short typically causes _____ circuit resistance
Answer: Lower than normal
Tech A says that an open circuit will typically higher current flow, which will blow the fuse
Answer: Neither A nor B
Two technicians are discussing voltage regulators
Answer: Neither A nor B
The________ prevents the starter motor from being driving by the engine once the engine starts, which would spin the amrature faster then is could handle
Answer: Overrunning clutch
________ are commonly used in the vehicles electrical system, especially for lights
Answer: Parallel Circuits
Since the heavy contacts are located between the input and the output terminals of the solenoid, where possible, it is best to measure the voltage drop from the __________ to the__________
Answer: Positive battery post; starter motor input
On modern Vehicles, what now controls the voltage regulator
Answer: Powertrain control module (PCM) or body control module (BCM)
The reduction in voltage and current to the load_________ the amount of electrical power to the load affecting its performance
Answer: Reduces
When doing a voltage drop test, you should do all exept
Answer: Remove the positive battery cable
Protection devises like fuses and fusable links are ______ meaning that if exsessive current flows hey ________
Answer: Sacrificial; will blow ar burn open and to be replaced
The magnetic fields from both winding work together to attract the _________ toward the main starter terminals in the solenoid cap
Answer: Solenoid plunger
The control circuit is made up of all of the following except
Answer: Starter cable
The stationary winding assembly in an alternator is called the
Answer: Stator
The ________ the magnetic field the _____ The alternator output
Answer: Stronger stronger
Tech A says amperage cannot exist without both voltage and resistance
Answer: Tech A
Tech A says test light are great for preforming simple tests. Tech B syas you can use a test light to check SRS circuits and computer Circuits
Answer: Tech A
Tech A says that a slow crank accomplished with high starter draw typically points to high electrical resistance in the starter circuit Tech B says that high starter draw current could be caused by high mechanical resistance from an engine fault such as a seized piston
Answer: Tech A
A voltage drop test is being preformed on the output wire of the alternator to the battery positive post
Answer: Tech B
Tech A says that good test of the alternator charging system is ti remove the battery positive cable off the battery post, and see if the engine dies. Tech B says that the practice of removing a battery cale connection while the engine is running can damage the electronics on this vehicle
Answer: Tech B
Tech A says that total resistance goes up as more parallel paths are added. Tech b says that total amperage goes up as more parallel pathe are added
Answer: Tech B
Two techs are discussing a higher than normal starter draw result
Answer: Tech B
All of the following are true about parallel circuits , Except
Answer: The sum of the voltage drops across individual resistors is equal to supply voltage
Which of the following is NOT a law for a parallel circuit?
Answer: Voltage changes at all common parallel circuit inputs.
Knowing the difference between an A- or B- type regulating circuit is necessary in order to properly bypass a _______ when diagnosing some charging systems
Answer: Voltage regulator
The ________monitors battery voltage and varies current flow through the rotor field circuit
Answer: Voltage regulator
When measuring the voltage drop on the ground side of the starter motor connect the red voltmeter lead to
Answer: a good ground on the starter motor housing
Jumper leads are used to extend connections to allow circuit readings or tests to be undertaken with
Answer: any of the above
When the starter motor starts load
Answer: it draws high current and produces high torque
The process of converting alternating current (AC) into direct current (DC) is called
Answer: rectification
In addition to recharging the battery the alternator is required to
Answer: supply current to the electrical circuits
When testing the voltage drop on the positive side of the starter the black voltmeter lead should be connected to
Answer: the positive terminal of the battery
Two technicians are discussing the use of a DMM. Technician A States that back-probing is a technique used to reduce the chance of damage while measuring. Technician B states that insulation piercing probes do not increase the chance of corrosion or damage the the conductor
Answer:Tech A
Technician A says when doing a voltage drop test, the voltmeter needs to be set to ohm. Technician B says current has to be flowing to do a voltage drop test. Who is correct?
Answer:Technician B
When testing for a voltage drop, always have the circuit
Answer:Turned on
When preforming a voltage drop test on a 12V blower motor circuit, the reading 2.7 volts across the fan switch when closed, What is the maximum voltage available at the fan?
Answer:9.3 volts
What is an example open circuit
Answer:A break in the electrical circuit
Resistance measurements should only be taken with powe__________, and ideally, with the component _______, from the circuit.
Answer:Disconnected; disconnected
The min/max setting is often used to measure vehicle battery voltage while:
Answer:Either A or B
All these statements are true about protection devices, except
Answer: You should always replace fuses and fusible links with higher rated ones.
A so-called three-phase bridge rectifier has a minimum of_______ to rectify the AC output of the stator windings to DC output from the certifier
Answer: 6 Diodes (3 positive, 3 negative)
As a voltmeter, the DMM can measure electrical voltage with circuits
Answer: All of the above
If only one side of the fuse lights the test lamp, then the fuse is
Answer: Blown
A voltage regulator _______, Thus controlling the strength of the magnetic field of rotating magnet
Answer: Both A and B
Tech A says that the pull-in winding short-circuited when the solenoid is fully engaged. Tech B says that the hold-in winding is used only to ensure that the moving contact continues to bridge the main starter terminals
Answer: Both A and B
Two technicians are discussing a charging output test
Answer: Both A and B
Two technicians are discussing a resistance measurement
Answer: Both A and B
Two techs are discussing a starter draw test where the starter draw current flow was substantially below specifications
Answer: Both A and B
A fan is either presses or slipped onto the rotor shaft to assist in cooling the rotor and stator winding and
Answer: Rectifier assembly
Tech A says that to read amperage the meter needs to be hoked up in series in a circuit. Tech B says that to read amperage at a load, placeone lead of the ammeter on the mput side of the load and the other lead on the output
Answer: Tech A
Tech A says that when resistance increases, current flow decreases. Tech B says that when voltage decreases, current increases
Answer: Tech A
Tech a says that the voltage regulator controls the strength of the rotor s magnetic field Tech b says that the voltage regulator is installed between the output terminal of the alternator and the positive terminal of the battery
Answer: Tech A
Two technicians are discussing non-powered test lights. Technician A says that the test light should be connected to the batteries + an- terminals to it is operational Technician B says hat the test light turnson if there is a problem in a circuit
Answer: Tech A
Technician A says you can use ohm's law in two ways to help diagnose electrical circuit faults. Technistin B says the first is by using it to preform the math to predict and verify the measurements
Answer: Tech A and B
Tech A says That an ohmmeter is used to measure the amount of current flowing in a circuit. Tech B says that to measure current, the DMM is connected in series with the load
Answer: Tech B
Tech A says wiring two resistors in parallel will cause a decrease in a current flow compared to wiring them in series
Answer: Tech B
Technician A says the slip ring and brushes carry the rectified current from the rotor to the output terminal of the alternator. Technician B says Slip rings and brushing aid in making an electrical connection to the rotating rotor assembly
Answer: Tech B
Two technicians are discussing an amperage measurement
Answer: Tech B
Two techs are discussing a vehicle's charging system running at 17.2 volts
Answer: Tech B
When testing the voltage drop on the positive side of the starter circuit (High current side), connect the red voltmeter lead to
Answer: The input of the starter motor
Which of the following is incorrect when talking about adding paths or legs in parallel circuits.
Answer: The voltage needs to go up as circuits are added
The revolving component of the starer is the
Answer: armature
Once a reading is obtained, it has to be interpreted and applied, in conjunction with knowledge of____, to diagnose the circuit being tested.
Answer:Electrical theory
What is the first step in setting up a DMM?
Answer:Know what you are testing volts, amps, or ohms
If the amperage is low then you know that one of two conditions is present either the voltage is _____ or the resistance ______.
Answer:Low; high
To achieve the most accurate reading, always selce the ____ range possible for the value being measured
Answer:Lowest
____________ Circuits are found in vehicles, such as in dash light dimer circuits, although they are not as common as _________ Circuits
Answer:Series-parallel;Parallel
It is important to understand that the ______ of the series voltage drops equals the supply voltage, as explained in kirchhoff s voltage law.
Answer:Sum
Technician A says an example of a series- parallel circuit is the dash light dimmer circuit. Technician B says when testing you only need to consider the voltage drop across the parallel branch
Answer:Tech A
