A2 Automatic Transmissions Q & A

1. A vibration occurs while driving a vehicle with an automatic transmission at normal speeds. This vibration does not occur during a stall test. Which of these is the cause.
A Torque Converter
B Drive Shaft
C Crankshaft Main Bearing
D EPC Solenoid
Answer B is correct. The vehicles drive shaft will be held stationary during a stall test.

2. There is a whining noise coming from the front of the transmission that increases with engine speed. This noise is present in all gears including park and neutral. The most likely cause of this is the:
A Planetary gear set
B Oil pump
C Output shaft
D Torque converter
Answer B is correct. A bad transmission pump makes a whining noise that increases with engine speed while in park or neutral.

3. An automatic transmission slips only when cold. As the vehicle warms up to operating temperature the transmissions performance returns to normal. Which of these is the cause?
A Oil pump
B Hardened seals
C Torque converter
D Input shaft end-play
Answer B is correct. Hardened seals allow fluid past when cold but as the vehicle warms the seals begin to function again. This transmission will need an overhaul to fix this problem.

4. Technician A says to clean the valve body with solvent and a lint free cloth. Technician B says if a spool valve is bent it can be straightened and reused. Who is correct?
A Technician A
B Technician B
C Both A and B
D Neither Technician A or B
Answer A is correct. The part should be cleaned in solvent and then dried with a lint free rag.

5. During a transmission fluid check the technician notices the ATF is milky in appearance. The is caused by which of the following?
A Overheating
B Slipping band
C Oxidation
D Oil cooler leak
Answer D is correct. The transmission fluid mixes with the coolant producing a milky color similar to a strawberry milkshake.

6. Two technicians are discussing shift feel. Technician A says a problem with the accumulator will create hard shifting. Technician B says a restricting orifice/check ball restricts the amount of fluid flow providing a smoother shift feel. Who is correct?
A Technician A
B Technician B
C Both A and B
D Neither Technician A or B
Answer C is correct. Both of these devices are designed to improve shift feel.

7. Technician A says that a shift solenoid is a hydraulically controlled device used by the transmission for shift control. Technician B says shift solenoids are computer controlled devices that can be diagnosed with a scanner. Who is correct?
A Technician A
B Technician B
C Both A and B
D Neither Technician A or B
Answer B is correct. They are computer controlled devices that can diagnosed with a scanner. If suspected a DMM is used to check resistance.

8. Technician A says a relay uses low current to control a high current circuit. Technician B says a relay may be electromechanical or solid state. Who is correct?
A Technician A
B Technician B
C Both A and B
D Neither Technician A or B
Answer C is correct. Both Technicians are correct.

9. Technician A says that the VSS (vehicle speed sensor) is driven by the input shaft of an automatic transmission. Technician B says that the parking pawl engages the input shaft to lock an automatic transmission. Who is correct?
A Technician A
B Technician B
C Both A and B
D Neither Technician A or B
Answer D is correct. Both the parking pawl and the vehicle speed sensor are associated with the output shaft.

10. Technician A says that a TP (throttle position) sensor is actually a potentiometer. Technician B says that as the throttle plate moves the resistance in the TP sensor changes. Who is correct?
A Technician A
B Technician B
C Both A and B
D Neither Technician A or B
Answer C is correct. The throttle position sensor is an input sensor for computer controls.

11. Technician A says a brake band is a stopping and holding device. Technician B says that hydraulic pressure is used to activate the servo and spring assembly in the brake band circuit. Who is correct?
A Technician A
B Technician B
C Both Technician A and B
D Neither Technician A or B
Answer C is correct. Both technicians are correct.

12. Automatic Transmissions use all of these pressures for shift control except:
A Governor
B Torque converter
C Vacuum modulator
D Throttle valve
Answer B is correct. A torque converter is a fluid coupling between the engine and the transmission.

13.Technician A says a TR sensor (Transmission Range Sensor) can be tested using an ohmmeter. Technician B says an improperly adjusted neutral safety switch can prevent a vehicle from starting. Who is correct?
A Technician A
B Technician B
C Both A and B
D Neither Technician A or B
Answer C is correct. Both Technicians are correct. An ohmmeter can be used to diagnose an analog TR Sensor. A neutral safety switch can prevent a vehicle from starting.

14. An excessive clunk is felt when placing an automatic transaxle into gear. Technician A says this could be excessive deflection in the final drive chain. Technician B says this could be worn universal joints. Who is correct?
A Technician A
B Technician B
C Both Technician A and B
D Neither Technician A or B
Answer A is correct. Chain deflection is checked by moving the chain in and marking the case, then moving the chain out and marking it again. The sum of the two equals total deflection. There is usually little deflection in a Transaxle/Final Drive chain.

15. All of these are types of transmission oil pumps except.
A Rotor
B Vane
C Diaphragm
D Gear
Answer C is correct. Automatic transmissions do not use diaphragm pumps.

This post was written by: Martin Hand

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Martin Hand

About Martin Hand

ASE Certified L1 Advanced Mastertech. Martin Hand has over 15 years experience in Asian and European Import Auto Repair. Specializing in electrical diagnosis, engine performance, AT/MT transmission repair/rebuild. Martin is also pursuing a degree in Computers Science & Information Systems starting at Portland Community College while he plans to transfer to OIT. Certified in Java application level programming, experienced with other languages such as PHP, Ruby, JavaScript and Swift. Martin has future plans of automotive diagnostic software development.