MTA Bus Maintainer Chassis Exam 2026-
Complete Study Guide with Actual Exam
Questions with Correct Answers and Detailed
Rationales
Question 1
All of the following are probable causes of an engine's failure to start EXCEPT:
A. Cylinders not wired in proper order
B. Poor coolant circulation
C. Resistance unit burned out
D. Defective condenser
Correct Answer: B
Rationale: Poor coolant circulation would cause overheating but would not prevent an
engine from starting. Cylinders not wired in proper order (firing order incorrect) would
prevent starting. A burned-out resistance unit would prevent proper ignition. A
defective condenser would cause ignition problems. Coolant circulation affects engine
temperature, not starting ability.
Question 2
In an expert system for offboard computer diagnosis, which stage of knowledge
acquisition in developing problem-solving rules occurs FIRST?
A. Implementation
B. Identification
C. Formalization
D. Conceptualization
Correct Answer: B
Rationale: The first stage of knowledge acquisition is Identification, where the
problem domain is defined and key concepts are identified. This is followed by
Conceptualization, Formalization, and Implementation. Identification is the initial
phase where the scope of the knowledge required is determined.
pg. 1
,Question 3
Some suspension units consist of tandem axles joined by a single cross support that also
acts as a vertical pivot for the entire unit. These units are known as:
A. Axials
B. Field frames
C. Bogies
D. Torsion bars
Correct Answer: C
Rationale: Bogies are suspension units consisting of tandem axles joined by a single
cross support that acts as a vertical pivot. They are commonly used in heavy-duty
vehicles and trailers. Torsion bars are a type of spring. Field frames and axials are not
standard terms for this component.
Question 4
In automotive electronics, the fractional duration that ignition points are closed is
known as:
A. Slip
B. Gain
C. Dwell
D. Delay
Correct Answer: C
Rationale: Dwell is the fractional duration (measured in degrees of distributor
rotation) that ignition points remain closed. During this period, current flows through
the primary winding of the ignition coil, building a magnetic field. Slip relates to
clutches and torque converters. Gain is an electronic amplification term.
Question 5
A brake system's warning lights may be tested by:
A. Testing the bulbs with an ohmmeter
B. Depressing the brake pedal and opening a wheel cylinder bleeder screw
C. Jumping the wires at the brake distributor switch assembly
D. Testing the system with an ammeter
Correct Answer: C
pg. 2
, Rationale: Jumping the wires at the brake distributor switch assembly will test the
warning light circuit by simulating the pressure differential condition that would
activate the switch. Testing bulbs with an ohmmeter only tests the bulb itself, not the
circuit. Opening a bleeder screw tests the hydraulic system, not the warning light.
Question 6
Of the following procedures performed prior to grinding a valve seat, which should be
performed FIRST?
A. Reaming
B. Grinding
C. Cutting
D. Lapping
Correct Answer: C
Rationale: Cutting (or refacing) the valve seat should be performed first before
grinding. Cutting removes the old seat material and creates a new surface. Reaming may
be needed for guides. Grinding is a finishing operation. Lapping is the final step for
seating the valve.
Question 7
What type of clutch is responsible for controlling a car's air conditioning compressor?
A. Centrifugal
B. Free-wheeling
C. Magnetic
D. Friction
Correct Answer: C
Rationale: A magnetic clutch (electromagnetic clutch) is used to engage and disengage
the air conditioning compressor. When energized, the magnetic field pulls the clutch
plate against the pulley, turning the compressor. Centrifugal clutches engage based on
RPM. Free-wheeling clutches allow one-way motion.
Question 8
Which of the following is a DISADVANTAGE associated with onboard computer
diagnostic systems?
pg. 3
Complete Study Guide with Actual Exam
Questions with Correct Answers and Detailed
Rationales
Question 1
All of the following are probable causes of an engine's failure to start EXCEPT:
A. Cylinders not wired in proper order
B. Poor coolant circulation
C. Resistance unit burned out
D. Defective condenser
Correct Answer: B
Rationale: Poor coolant circulation would cause overheating but would not prevent an
engine from starting. Cylinders not wired in proper order (firing order incorrect) would
prevent starting. A burned-out resistance unit would prevent proper ignition. A
defective condenser would cause ignition problems. Coolant circulation affects engine
temperature, not starting ability.
Question 2
In an expert system for offboard computer diagnosis, which stage of knowledge
acquisition in developing problem-solving rules occurs FIRST?
A. Implementation
B. Identification
C. Formalization
D. Conceptualization
Correct Answer: B
Rationale: The first stage of knowledge acquisition is Identification, where the
problem domain is defined and key concepts are identified. This is followed by
Conceptualization, Formalization, and Implementation. Identification is the initial
phase where the scope of the knowledge required is determined.
pg. 1
,Question 3
Some suspension units consist of tandem axles joined by a single cross support that also
acts as a vertical pivot for the entire unit. These units are known as:
A. Axials
B. Field frames
C. Bogies
D. Torsion bars
Correct Answer: C
Rationale: Bogies are suspension units consisting of tandem axles joined by a single
cross support that acts as a vertical pivot. They are commonly used in heavy-duty
vehicles and trailers. Torsion bars are a type of spring. Field frames and axials are not
standard terms for this component.
Question 4
In automotive electronics, the fractional duration that ignition points are closed is
known as:
A. Slip
B. Gain
C. Dwell
D. Delay
Correct Answer: C
Rationale: Dwell is the fractional duration (measured in degrees of distributor
rotation) that ignition points remain closed. During this period, current flows through
the primary winding of the ignition coil, building a magnetic field. Slip relates to
clutches and torque converters. Gain is an electronic amplification term.
Question 5
A brake system's warning lights may be tested by:
A. Testing the bulbs with an ohmmeter
B. Depressing the brake pedal and opening a wheel cylinder bleeder screw
C. Jumping the wires at the brake distributor switch assembly
D. Testing the system with an ammeter
Correct Answer: C
pg. 2
, Rationale: Jumping the wires at the brake distributor switch assembly will test the
warning light circuit by simulating the pressure differential condition that would
activate the switch. Testing bulbs with an ohmmeter only tests the bulb itself, not the
circuit. Opening a bleeder screw tests the hydraulic system, not the warning light.
Question 6
Of the following procedures performed prior to grinding a valve seat, which should be
performed FIRST?
A. Reaming
B. Grinding
C. Cutting
D. Lapping
Correct Answer: C
Rationale: Cutting (or refacing) the valve seat should be performed first before
grinding. Cutting removes the old seat material and creates a new surface. Reaming may
be needed for guides. Grinding is a finishing operation. Lapping is the final step for
seating the valve.
Question 7
What type of clutch is responsible for controlling a car's air conditioning compressor?
A. Centrifugal
B. Free-wheeling
C. Magnetic
D. Friction
Correct Answer: C
Rationale: A magnetic clutch (electromagnetic clutch) is used to engage and disengage
the air conditioning compressor. When energized, the magnetic field pulls the clutch
plate against the pulley, turning the compressor. Centrifugal clutches engage based on
RPM. Free-wheeling clutches allow one-way motion.
Question 8
Which of the following is a DISADVANTAGE associated with onboard computer
diagnostic systems?
pg. 3
