Deck 21: Electronically Controlled Automatic Transmissions Ecats

Question 1

Which of the following is generally true of a non-latching solenoid?

A) spring-loaded to a default off position
B) spring-loaded to a default on position
C) blocks oil flow when energized
D) modulates oil flow when not energized

Answer 1

A

Question 2

Which of these clutches puts an Allison WT drop-box into extra-low range?

A) C4
B) C5
C) C6
D) C7

Answer 2

C

Question 3

Which of the following are advantages of using secondary submodulation of solenoids?

A) heat in the solenoid coil is minimized
B) solenoid performance is more consistent during operating variables
C) both A and B
D) neither A nor B

Answer 3

C

Question 4

When does an Allision WT transmission use fast adaptive mode?

A) when it has close-ratio gearing
B) when it has standard gear ratios
C) when programmed to do so after a rebuild
D) whenever hard acceleration is required

Question 5

A solenoid that requires a momentary voltage source to change position,then holds position and requires reverse current pulse to revert to its original position known as?

A) Latching solenoid
B) Non-latching solenoid
C) pulse actuator
D) induction sensor

Question 6

Which of the following terms are used by Allison to describe the solenoids used in WT controls?

A) latching and non-latching
B) normally-open and normally-closed
C) fast-adaptive and slow-adaptive
D) energized-to-run and energized-to-unlatch

Question 7

When Allison WT drop-box output is split between the front and rear axles,how much of the available torque would normally go to the front axle?

A) 70%
B) 600%
C) 50%
D) 30%

Question 8

What is the minimum number of planetary gearsets used in a Caterpillar CX ECAT?

A) One
B) Two
C) Three
D) Four

Question 9

How many planetary gearsets are there in an Allison TC10 ECAT?

A) None
B) One
C) Two
D) Three

Question 10

What is used to signal accelerator position to an Allison ECAT electronics?

A) analog potentiometer type TPS
B) digital Hall-effect TPS
C) governor feedback signal
D) either A or B

Question 11

Which of the following Allison WT clutches are designed to transmit rotating torque to the planetary gears?

A) C1 and C2
B) C2 and C3
C) C3 and C4
D) C6 and C7

Question 12

Technician A says that an Allison TC10 splits input torque between a pair of countershafts.Technician B says that it is possible to transmit output torque from a TC10 bypassing the gearbox module.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 13

Which of the folowing is a full-authority ECAT?

A) Allison WT
B) Allison TC
C) Caterpillar CX
D) All of the above

Question 14

Which of the following WT clutches are designed to hold at least one member of a planetary gearset stationary?

A) C1 and C3
B) C2 and C4
C) C3,C4,and C5
D) C2,C3,and C5

Question 15

What is the minimum number of planetary gearsets used in an Allison WT transmission?

A) One
B) Two
C) Three
D) Four

Question 16

What is the source address (SA)of the transmission ECU on the J1939 data bus?

A) 00
B) 01
C) 02
D) 03

Question 17

Which of the following statements accurately describe primary and secondary modulation of solenoids in a WT transmission?

A) primary modulation controls on-time at a frequency of 63 Hz
B) secondary modulation maintains an optimal current flow at 7,812 Hz
C) primary modulation has a variable duty cycle
D) all of the above

Question 18

Which of the following descriptions best describes the older Allison CEC family of electronically-managed transmissions?

A) full-authority,electronically-managed
B) partial-authority,electronically managed
C) full-authority,hydromechanically-controlled
D) partial-authority electronics using an all-new modular gearset platform

Question 19

When ordering parts for any WT transmission,what information must be communicated accurately to identify the transmission?

A) vehicle OEM,model,and year of manufacture
B) all 17 characters from the vehicle VIN
C) transmission model,serial,and part numbers
D) transmission model and the date placed in service

Question 20

Which of the following true statements is true regarding solenoid operation in an Allison ECATs?

A) non-latching solenoids permit hydraulic flow only when electrically energized
B) latching solenoids can be switched with either straight or reversed polarity
C) latching solenoids replace the shift signal valves used in non-electronic transmissions
D) all of the above

Question 21

How many forward ratios are there in a Caterpillar CX28 transmission

A) four
B) five
C) six
D) continuously variable

Question 22

Which of the following best describes the function of the Allison WT serial communications interface (SCI)?

A) enables one-way J1939 bus communications
B) enables two-way J1939 bus communications
C) connects WT ECU directly to digital display (DD)
D) connects WT ECU directly to a digital diagnostic reader (DDR)

Question 23

How is the PTO mode in an Allison World Transmission managed?

A) activated by the operator
B) managed by the ECU
C) may be continuous whenever there is transmission input
D) any of the above

Question 24

When TranSynd synthetic oil is used in ECATs,Allison state that the oil change intervals can be extended by ____ times.

A) one: treat as Dexron
B) two
C) four
D) five

Question 25

How many solenoids are energized in a WT transmission when it is in neutral?

A) none
B) 1
C) 2
D) 3

Question 26

After the maximum number of codes are logged in a WT ECU,what happens to new codes that are detected?

A) added and the oldest non-active code is dropped
B) if all codes are active,the lowest-priority code is dropped
C) new code cannot be added until existing codes are retrieved
D) both A and B

Question 27

What lubricant do Caterpillar recommend for use in their CX family of onhighway transmissions?

A) synthetic E-500
B) Dexron II
C) Dexron III
D) synthetic AT-1

Question 28

How many clutches must be applied for a WT transmission to operate in either forward or reverse?

A) 1
B) 2
C) 3
D) 4

Question 29

Which of the following are serial communications interface (SCI)inputs to the WT electronics?

A) transmission tailshaft speed
B) transmission sump temperature
C) throttle position
D) range position

Question 30

How many ranges are overdrive ratios in a 6-speed World Transmission?

A) none
B) 1
C) 2
D) 3

Question 31

In which of the three Allison TC10 modules is a single planetary gearset located?

A) Torque conveter module
B) Input module
C) Gearbox module
D) Output module

Question 32

When input torque is managed to bypass both countershafts in an Allison TC10 transmission,which of the following gear ratios would it be operating in?

A) First
B) Second
C) Fourth
D) Fifth

Question 33

Technician A says that a Caterpillar ADEM controller module is used to manage the CX family of Caterpillar on-highway transmissions.Technician B says the reprogramming,calibration,and troubleshooting software required for Caterpillar CX transmission is ET.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 34

In the event of a total loss of electrical supply to a World Transmission,what would result?

A) cease to function
B) revert to hydromechanical operation
C) default to limp home mode
D) both B and C

Question 35

Which of the following are serial communications interface (SCI)outputs from the WT ECU?

A) cruise control status
B) road speed limit status
C) kickdown signal
D) transmission output speed

Question 36

Technician A says that when the WT digital display (DD)is blank,the reason could be a problem in the electrical circuit to the shift selector.Technician B says that when the WT DD is blank,the data link may have failed.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 37

Technician A says that the WT mainshaft is splined to the rotating clutch module.Technician B says that the mainshaft connects all three planetary gearsets in a WT transmission.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 38

Technician A says that Allison recommend the use of TranSynd in ECATs.Technician B says that Dexron is no longer approved for use in WT transmissions.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 39

How many forward ratios are there in a Caterpillar CX35 vocational transmission?

A) four
B) five
C) six
D) eight

Question 40

What is indicated when the WT Digital Display is showing a flashing 3?

A) transmission is about to shift into range 3
B) transmission is in range 3 awaiting either an upshift or downshift
C) trouble code 3 has been set in the ECU fault log
D) shift will occur in 3 seconds

Question 41

Where is the main pressure tap located on a Caterpillar CX transmission?

A) filter pad housing
B) ECPC valve housing
C) shift tower
D) ECU heat sink

Question 42

Technician A says that a Caterpillar CX transmission should be recalibrated each time the ECPCs are serviced.Technician B says that in order to recalibrate a Caterpillar CX transmission,Caterpillar ET and a road test are required.Who is correct?

A) Technician A only
B) Technican B only
C) Both A and B
D) Neither A nor B

Question 43

Technician A says that the Allison TC10 gearbox module does not require the use of synchromizers because all of the gears rotate in the same direction.Technician B says that both countershafts in the TC10 rotate in the same direction.Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 44

What is used to manage main pressure in an ECAT?

A) main pressure regualator
B) modulator valve
C) governor valve
D) backfill valve

Question 45

How many reverse ratios are there in an Allison TC10?

A) One
B) Two
C) Five
D) Ten

Question 46

How many forward ratios are there in an Allison TC10?

A) Five
B) Ten
C) Twelve
D) Twenty

Question 47

Technician A says that the ECPC valves used on Caterpillar CX transmissions are PWM controlled.Technician B says that Caterpillar CX transmission hydraulic troubleshooting is facilitated by pressure taps located at key points in the hydraulic circuit Who is correct?

A) Technician A only
B) Technician B only
C) Both A and B
D) Neither A nor B

Question 48

Which of the following correctly describes the two output options of the output module on the Allison TC-10?

A) low range and direct drive
B) underdrive and overdrive
C) low range and high range
D) deep reduction and low reduction

Question 49

What is required to access DTCs in an Allison ECAT?

A) ET
B) DMM
C) DDD
D) DOC

Question 50

What type of fluid level sensor is used to signal sump level on a Caterpillar CX transmission?

A) rheostat variable resistor float
B) potentiometer
C) optical
D) Hall-effect

Question 51

Which of the following should be true of a powershift transmission?

A) shifts under full acceleration without breaking driveline torque
B) zero slip loss during ratio upshifts
C) lower skill level required of driver
D) all of the above

Question 52

Which of the following pressure values would be within specification for main pressure in a Caterpillar CX transmission?

A) 125 psi
B) 250 psi
C) 350 psi
D) 700 psi

Question 53

What effects clutch control in a Caterpillar CX transmission?

A) non-latching solenoids
B) latching solenoids
C) PWM actuated ECPCs
D) V-Ref

Question 54

When using a DMM in resistance mode across terminals Cand D on a 9-pin J1939 receptacle,40 ohms is displayed on the meter.Which of the following is most likely?

A) One missing terminating resistor
B) Both terminating resistors missing
C) Three terminating resistors on the bus
D) The bus is down

Question 55

What Allison software component can be used to identify a transmission problem before it results in an actual breakdown?

A) DTCs
B) prognostics
C) audit trail
D) adaptive logic

Question 56

What is used to manage variable bleed proportioning solenoids?

A) V-Bat
B) V-Ref
C) main pressure
D) PWM signal

Question 57

On an Allison TC10,what do the 4th and 9th ratio options have in common?

A) torque is split evenly though the countershafts
B) torque is multiplied through the countershafts
C) torque is routed through the left countershaft
D) input torque bypasses both countershafts to the output module