Cont Electronico 24H CAT

8/19/2019 Cont Electronico 24H CAT

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• Lab A

• Lab B

• Lab C

• Slides 2 -14

• Lab D

• Slides 7 - 14

• Lab F

• Lab E

• Slide 15

• Posttest

MODULE OBJECTIVES

Students must view the H-Series Motor Grader Introduction and

Hydraulic and Transmission Systems video tapes before completing the

module objectives. After completing this module, the student will be ableto:

1. Given an operation and maintenance guide or a service manual

module and motor grader, locate and identify the major power train

components during a lab exercise.

2. Given the video tape "H-Series Motor Graders--Hydraulic and

Transmission Systems" and the Lab B Worksheets, list the location

and function of the transmission system components during a

classroom lab exercise.

3. Given class notes, a hydraulic schematic, and a selector and pressure

control valve sectional view, identify the transmission hydraulic

system components during a classroom lab exercise.

4. Given a transmission hydraulic system schematic, trace the flow of oil

through the system during operation in FIRST FORWARD during a

classroom lab exercise.

5. Given a motor grader, the appropriate service module and tooling, list

the logged and active electrical faults in the Transmission ECM

during a lab exercise.

6. Given a motor grader, the appropriate service module and tooling, test

and record the following pressures on a lab worksheet: supply pressure, lubrication pressure, pilot pressure, eight clutch pressures,

and differential lock pressure.

7. Without using any notes, identify the system components and, from a

list, identify the cause and/or effect of a component or system

malfunction during a posttest.

SEEV2613 - 2 - Student Materials

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BACKGROUND

INFORMATION

Lab A: Major Component Location Identification

Shop Lab Exercise

Procedure:

After viewing the video tape "H-Series Motor Graders--Introduction,"

walk around the machine and identify the components listed on the lab

worksheets and write the component letter in the blank next to the

corresponding component listed.

Lab A Worksheets I and II

Motor Grader


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INDIVIDUAL EXERCISE

MATERIALS NEEDED


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D i r e c t i o n s : W r i t e t h e l e t t e r o f t h e c o m p o n e n t

i n t h e c o r r e c t b l a n k .

P a r k i n g B r a k e

T r a n s m i s s i o n

L e f t F i n a l D r i v e

R i g h t T a n d e m

D r i v e S h a f t

D i f f e r e n t i a l

R i g h t F i n a l D r i v e

L e f t T a n d e m


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F R O N T

O F

M A C H I N E

A

C

B

D

E

F

G

H

L a b A : M a j o r P o w e r T r a i n

C o m p o n e n t L o c a t i o n

I d e n t i f i c a t i o n W o r k s h e e t I


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D i r e c t i o n s : W r i t e t h e l e t t e r o f t h e c o m p o n e n t

i n t h e c o r r e c t b l a n k .

C o n t r o l V a l v e

D i f f e r e n t i a l H o u s i n g S u m p

C h a r g i n g S e c t i o n

T r a n s m i s s i o n C a s e

S c a v e n g e S e c t i o n

F i l t e r

P o w e r T r a i n O i l C o o l e r


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A

F R O N T

O

F M A C H I N E B

D

C

E F

G

L a b A : M a j o r P o w e r T r a i n

C o m p o n e n t L o c a t i o n

I d e n t i f i c a t i o n W o r k s h e e t

I I


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Lab B: Component Location and Function

Classroom Exercise

Procedure:

View the Transmission Section of the video tape "H-Series Motor Graders

--Hydraulic and Transmission Systems." Fill out the worksheets as you

watch the tape.

Class Notes

Power Train Service Manual Module

Lab B Worksheets


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BACKGROUND

INFORMATION

INDIVIDUAL EXERCISE

MATERIALS NEEDED


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Lab B: Component Location and Function Worksheet

Directions: During the video presentation, use this sheet to take notes on the function of each

component.

PUMP SYSTEM COMPONENTS:

Transmission Pump -

Scavenge Screen and Magnetic Filter -

Charging Screen and Magnetic Filter -

Filter -

Differential Lock Group -

Centershift Lock Group -

CONTROL VALVE COMPONENTS:

Control Valve -

• Main Relief Valve -

• Priority Reducing Valve -

• Manual Modulation Valve (Inching Valve) -


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Lab B: Component Location and Function Worksheet (continued)

• Cooler Relief Valve -

• Lube Relief Valve -

• Parking Brake -

Manual Modulation Pressure Switch -

Transmission Shift Lever -

Transmission ECM -

Diagnostic Connector -

Transmission Indicator Lamp -

Transmission Output Speed (TOS) Sensor -


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H 7

E 4

F 6

G 5

N 1 R

2 R

3 R

4 R

5 R

6 R

N 1 F

2 F

3 F

4 F

5 F

6 F

7 F

8 F

P A R K

A B C D

E F G H

A B C D 3 1 2 8

.

T Y P I C A L H - S

E R I E S M O T O R G R A D

E R T R A N S M I S S I O

N H Y D R A U L I C S Y

S T E M

F I R S T S P E E D F O R W A R D

S

F

R E P

Q

D

C

A N M

L

O

G

H K

J

I

B

L a b C : T r a n s m i s s i o n H y

d r a u l i c S y s t e m C o m p o n e

n t I d e n t i f i c a t i o n u s i n g t h e

H y d r a u l i c S c h e m a t i c W o

r k s h e e t I

D i r e c t i o n s : W r i t e t h e n a m e o f t h e c o m p o n e n t i n t h e b l a n k n e x

t t o t h e n a m e o f t h e c o m p o n e n t

o n W o r k s h e e t I I u s i n g t h e s c h e m a t i c o n

W o r k s h e e t I .


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Charging Section

Differential Lock Valve

Centershift Lock Group

Elevated Drain Relief Valve

Filter

Scavenge Section

Transmission Lube Relief Valve

Priority Reducing Valve

Cooler

Manual Modulation Clutch Pressure Switch

Transmission Pump

Transmission Sump

Transmission Lube

Main Relief ValveCooler Bypass

Manual Modulation Valve

Differential Sump

Centershift Lock Solenoid

Screens and Magnetic Filters

1.

2.

3.

4.

5.

6.

7.

8.

9.

10.

11.

12.

13.

14.15.

16.

17.

18.

19.

Lab C: Transmission Hydraulic System Component Identification using theHydraulic Schematic Worksheet II

Directions: Write the letter of the component in the blank next to the name of the component on

Worksheet II using the schematic on Worksheet I.


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L a b C : T r a n s m i s s i o n H y

d r a u l i c S y s t e m C o m p o n e

n t I d e n t i f i c a t i o n u s i n g t h e

H y d r a u l i c S c h e m a t i c - C o m m o n

S e l e c t o r a n d P r e s s u r e C o

n t r o l V a l v e C o m p o n e n t s W o r k s h e e t I I I

D i r e c t i o n s : W r i t e t h e l e t t e r o f

t h e c o m p o n e n t i n t h e b l a n k n e x

t t o t h e n a m e o f t h e c o m p o n e n t .

A

B

C

D

E

F

G

H

I n i t i a l P r e s s u r e A d j u s t m

e n t S c r e w

D e c a y O r i f i c e

M o d u l a t i o n O r i f i c e

S e l e c t o r S p o o l

M

o d u l a t i o n R e d u c i n g V a l v e

S

o l e n o i d

L

o a d P i s t o n

C

l u t c h


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Lab D: Tracing Oil Flow through the TransmissionHydraulic System

Classroom Exercise

Procedure:

Fill out the worksheets. The following colors should be used to trace the

different paths the oil takes through the system:

Red - Pump supply pressure

Red and White Stripes - Clutch pressure

Red Dots - Pilot pressure

Blue - Blocked oil

Green - Tank or case drain

TRANSMISSION HYDRAULIC SYSTEM CONDITION

• First Speed Forward

Trace the flow of oil during the condition listed above on the

corresponding lab worksheet.

Lab D Worksheets I and II

Colored Pencils


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BACKGROUND

INFORMATION

INDIVIDUAL EXERCISE

MATERIALS NEEDED


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L a b D : T r a c i n g O i l F l o w

t h r o u g h t h e T r a n s m i s s i o n S e l e c t o r a n d P r e s s u r e C

o n t r o l V a l v e H y d r a u l i c S y s t e m

( O u t e r D e c k ) W o r k s h e e t

I

D i r e c t i o n s : T r a c e t h e f l o w o f

o i l d u r i n g F i r s t S p e e d F o r w a r d u s i n g d i f f e r e n t c o l o r e d p e n c i l s t o s h o w t h e p a t h s .


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L a b D : T r a c i n g O i l F l o w

t h r o u g h t h e T r a n s m i s s i o n S e l e c t o r a n d P r e s s u r e C

o n t r o l V a l v e H y d r a u l i c S y s t e m

( I n n e r D e c k ) W o r k s h e e t

I I

D i r e c t i o n s : T r a c e t h e f l o w o f

o i l d u r i n g F i r s t S p e e d F o r w a r d u s i n g d i f f e r e n t c o l o r e d p e n c i l s t o s h o w t h e p a t h s .


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Lab E: Transmission Electrical System

Shop Lab Exercise

Procedure:

Fill out the worksheets.

Perform the following tests listed in the Power Train Systems Operation,

Testing and Adjusting Service Manual Module for the lab machine used:

Worksheet I • Electrical Faults using the ECAP

Worksheet II • Electrical Faults using the Transmission Indicator Lamp

Worksheet III • Electrical Component Quiz

Worksheet IV • Transmission ECM Inputs and Outputs Quiz

Class Notes

Lab C Worksheets I to IV

Lab C Student Handout

1 - 9U7330 Multimeter

1 - 8T8697A Electronic Control Analyzer Programmer (ECAP)1 - 7X1700 Communication Adapter Group

1 - 7X1851 Cable

1 - 7X1570 Cable

1 - 7X1703 Plate Group

1 - Piece of insulated 16 gauge wire approximately 150 mm (6 in.)

long

1 - Set of colored pencils per student

1 - Electrical Schematic for the machine used in class


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BACKGROUND

INFORMATION

INDIVIDUAL EXERCISE

MATERIALS NEEDED


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LAB E: ELECTRICAL FAULTS USING THE ECAP

WORKSHEET I

__________MACHINE MODEL DATE_________________

__________VEHICLE HOURMETER ____________________ SERIAL NUMBER

__________TRANSMISSION ECM HOURMETER

__________TRANSMISSION IDENTIFICATION CODE

DIAGNOSTIC CODES

CODES

NUMBER OF LOGGED AT CURRENTCID/FMI DESCRIPTION OCCURRENCES FIRST LAST STATUS

1.______________________________________________________________________

2.______________________________________________________________________

3.______________________________________________________________________

4.______________________________________________________________________

5.______________________________________________________________________

6.______________________________________________________________________

7.______________________________________________________________________

8.______________________________________________________________________

9.______________________________________________________________________

10. ____________________________________________________________________

11. ____________________________________________________________________

12. ____________________________________________________________________

13. ____________________________________________________________________

14. ____________________________________________________________________

15. ____________________________________________________________________


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LAB E: ELECTRICAL FAULTS USING THE

TRANSMISSION INDICATOR LAMP

WORKSHEET II

__________MACHINE MODEL DATE_________________

__________VEHICLE HOURMETER ____________________ SERIAL NUMBER

__________TRANSMISSION IDENTIFICATION CODE

DIAGNOSTIC CODES

FLASH CURRENT

CID/FMI DESCRIPTION CODE STATUS

1.______________________________________________________________________

2.______________________________________________________________________

3.______________________________________________________________________

4.______________________________________________________________________

5.______________________________________________________________________

6.______________________________________________________________________

7.______________________________________________________________________

8.______________________________________________________________________

9.______________________________________________________________________

10. ____________________________________________________________________

11. ____________________________________________________________________

12. ____________________________________________________________________

13. ____________________________________________________________________

14. ____________________________________________________________________

15. ____________________________________________________________________


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Lab E: Electrical Quiz Worksheet III

DIRECTIONS: Using an electrical schematic for a 140H Motor grader, complete the following

individual exercises:

1. Locate the Inching Pedal Pressure Switch on the schematic.

Grid location

2. What is the part number of the Inching Pedal Pressure Switch?

3. The actuate pressure is , the deactuate pressure is , and the

normal condition for the inching pedal pressure switch is .

4. What gauge wires are attached to the switch in question 3?

a. 14 gauge c. 18 gauge

b. 16 gauge d. 20 gauge

5. What is the letter and part number of the Machine Harness Assembly for the switch in question 3?

6. What is the Electronic Transmission Shift Control Service Manual module literature number?

7. Locate the Transmission Diagnostic Connector on the schematic. List the schematic grid location.

8. What type of connector is used for the Transmission Diagnostic Connector?

a. Sure-Seal connector

b. Deutsch connector

c. Hard wire connections

9. Locate the Service Tool Connector on the schematic. List the schematic grid location and the partnumber. Grid location and Part Number

10. Locate the Transmission Speed Sender on the schematic. List the schematic grid location.

Grid location


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11. What is the part number of the Transmission Speed Sender Harness?

a. 104-7842 b. 104-8588

c. 115-3600 d. none of the above

12. What type of connector is used to connect the Transmission Speed Sender to the machine harness?

a. Sure-Seal connector

b. Deutsch connector

c. Hard wire connections

13. What is the wire number and color of the Transmission Speed Sender signal wire?

14. What size fuse is used to protect the Transmission ECM, and what is the grid

location of the fuse?

15. Which Transmission Solenoids are energized in First Speed Reverse?

16. Locate the Coolant Temperature Sender on the schematic. What does the dashed ground symbol

represent (explain)?

17. On the Coolant Temperature Sender, what is the color of the wire that connects to the Coolant

Temperature Gauge?

18. Locate the Articulation Sender on the schematic. List the schematic grid location.

Grid location

19. The right side of the schematic represents what part of the machine?

20. On the schematic, what does the color RED represent?

21. Locate the Transmission Indicator Lamp on the schematic. List the schematic grid location.

Grid location

22. What is the name of the "N" harness?

23. What is the part number of a 10 amp fuse?

24. What component sends its signal to the tachometer?

25. What is unique about wires 710-GN and 202-BK?


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L a b E : I d e n t i f y i n g T r a n s m i s s i o n E C M I n p u t s a n d

O u t p u t s W o r k s h e e t I V

D i r e c t i o n s : I d e n t i f y e a c h

o f t h e i n p u t s a n d o u t p u t s o f t h e T r a n s m i s s i o n E C M a n d w r i t e t h e n a m e i n t h e b l a n

k . U s e t h e

e l e c t r i c a l s c h e m a t i c a n d S t u d e n t H a n d o u t f o r r e f e r e n c

e .


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S E R V I C E T O O L

7 8

P

1 0

1 1

1 2

1 3

1 4

1 5

1 6

1 7

2 0

2 6 - 2 7

E C M

H - S E R I E S M O T O R G R A D E R

T R A N S M I S S I O N E L E C

T R O N I C C O N T R O L

M O D U L E

3

2 8 - 4 0 4 6

1 8

1 9

2 1 - 2 3

6 5

2 5

M P H


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Lab E: Transmission Electrical System Student Handout

I. DEFINITIONS, ACRONYMS, AND ABBREVIATIONS

1. CAT Data Link - A medium speed digital data communication link which is used to providesharing of sensor information between electronic controls and service tools on Caterpillar

Machines.

2. Component Identifier (CID) - A three-digit number that is displayed to the technician on the

ECAP Service Tool diagnostic display during servicing. The number indicates the system

component in question.

3. Countershaft Transmission - The transmission used on the H-Series Motor Graders and is shifted

by means of electro-hydraulic valves which provide clutch control oil.

4. Electronic Control Analyzer Programmer (ECAP) - The Service Tool used by the technician to

gain access to the system status and diagnostic information stored in the Transmission ECM.

5. Transmission Electronic Control Module (ECM) - The control is located below the operator’s

seat and processes the input information which then directs the proper electrical signals to the

appropriate output devices for speeds, directions, and diagnostics.

6. Electronic Monitoring System (EMS) - A dash-mounted panel which alerts the operator to

various vehicle status conditions.

7. Failure Mode Identifier (FMI) - A two-digit "F" code that is displayed to the technician on the

ECAP Service Tool diagnostic display during servicing. The number indicates the failure mode of

the related component.

8. Transmission Output Speed (TOS) - A transmission signal generated by a magnetic pickup on

the transmission output shaft.

II. ELECTRICAL INPUTS

1. Battery Voltage - A two wire input which provides 24 VDC nominal to drive the electroniccircuits within the ECM and all the external solenoids.

2. Start Switch Input - A single wire input that provides a battery voltage signal when the key start

switch is in the START position.

3. Transmission Shift Lever - Mechanical lever which selects PARK, NEUTRAL, one to eight

FORWARD and one to six REVERSE speeds and then directs the electrical signal to the

transmission ECM. The unit is sealed and has no serviceable components. The unit also actuates

the parking brake.


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Lab E: Transmission Electrical System Student Handout (continued)

4. Manual Modulation Clutch Pressure Switch - A normally open switch which is located on the

outermost valve body and monitors the supply pressure to the directional clutch stations A, B and C.

When the manual modulation (or inching) pedal is depressed, the manual modulation valve insidethe transmission control valve disengages or reduces the power transmitted to the drive wheels by

reducing the supply pressure to the three directional modulating reducing valves. The pressure

switch will open and/or close at approximately 70 kPa (10 psi) and provides the ECM with the

status of the manual modulation pedal.

5. Transmission Output Speed (TOS) Sender - Located on the bottom right of the transmission and

provides an electrical signal to the transmission ECM for engine overspeed information and then to

the speedometer for ground speed.

6. Diagnostic Connector - A Sure-Seal connector which is located to the right of the transmission

ECM and is used to diagnose faults in the transmission electrical system.

III. ELECTRICAL OUTPUTS

1. Transmission Solenoids - These solenoids are powered by 24 VDC from the ECM and are engaged

when the ECM determines the correct time to be ON.

2. Starter Relay - When the key start switch is turned to the START position, 24 VDC is directed to

the starter relay to engage the starter motor if the transmission shift lever is not in a speed or

direction.

3. Back-up Alarm - When the transmission shift lever is moved to a REVERSE speed, the ECM provides power for the back-up alarm.

4. Dual Horsepower Solenoid (VHP) - When the transmission shift lever is moved to four to eight

FORWARD or three to six REVERSE speeds, the ECM provides power for the dual horsepower

solenoid. If the model is a 143H or 163H All Wheel Drive machine, the ECM will provide power to

the dual horsepower solenoid any time the AWD mode switch is moved to MANUAL or

AUTOMATIC.

5. Output to EMS (pin 8 on ECM) - The transmission ECM is connected to the EMS panel lamp

position 5 which is called the "Transmission Electrical Fault lamp." If a problem is detected in the

transmission ECM system, the ECM disconnects the ground and the lamp illuminates.

6. Output to the EMS (pin 7 on ECM) - The transmission ECM is connected to pin 9 (Neutral) at the

EMS control. Pin 9 has a function called "Program Code 1" and is used to control the category of

Alert Indicator 7 which is the Parking Brake indicator. Depending on the condition, the Parking

Brake can be either a Category 1 or 3 indication.

7. Service Tool Connector - A two wire digital data communication link that allows two way

communication of the ECAP or service tool with the transmission ECM.


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8. Transmission Indicator Lamp - Used in conjunction with the diagnostic connector to visually

flash light code sequences when diagnosing transmission electrical system faults.

9. Buffered Transmission Output Speed (TOS) - The output from the transmission speed sender

after it goes through the ECM and then to the speedometer.

IV. MODES OF OPERATION

1. Power-up Operation - Upon power-up, solenoids D and G are energized and all other solenoids are

de-energized.

2. Start Operation - The Transmission ECM has a neutral-start feature. The operator controlled key

start switch is an input to the ECM with the starter relay being powered by an output from the ECM.

This feature allows the ECM to inhibit starting the machine if certain conditions are not met. The

shift lever must be in NEUTRAL or PARK before the ECM will allow the starter relay to be

energized.

3. Upshift Operation - When the shift handle is moved from the current speed position to a higher

speed position, the ECM will shift the transmission immediately. If an upshift is attempted with the

inching pedal depressed, no action by the ECM is taken until the inching pedal is released.

4. Downshift Operation - When the shift handle is moved from the current speed position to a lower

speed position, the ECM will shift the transmission immediately. If an overspeed condition occurs,

the transmission is shifted to the lowest speed possible using special shift points. If the TOS has not

lowered below an overspeed condition, the ECM will upshift to the appropriate speed. If adownshift is attempted with the inching pedal depressed, no action is taken until the inching pedal is

released. After the pedal is released, the ECM will determine the proper speed.

5. Shift Out of Neutral - When the shift handle is moved from NEUTRAL into a position which

matches the direction the machine is moving, the ECM will first check the TOS and determine if the

requested speed can be obtained without overspeeding the transmission. If no overspeed condition

will occur, then the shift is made.

If a shift out of NEUTRAL to the requested speed will cause an overspeed condition, the ECM will

shift to the lowest speed possible.

When a shift out of NEUTRAL is attempted with the inching pedal depressed, one of two things

will happen. 1. If the TOS is below the FIRST speed shift point, the shift is made immediately. 2.

If the TOS is above the FIRST speed shift point, NO SHIFT will be made until the TOS drops

below the FIRST speed shift point or the inching pedal is released.

6. Shift Into Neutral - When the shift handle is moved from a speed position to NEUTRAL, the ECM

will shift the transmission to NEUTRAL immediately. The status of the inching pedal or the TOS

rpm does not matter.


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V. SPECIFIC FAILURE MODES

1. Solenoid Faults - The detection of a system fault which prevents energizing a solenoid for theselected speed will result in the ECM causing the transmission to go to NEUTRAL by using

solenoids D and G (preferred), solenoid D, solenoid G, or all solenoids OFF (least preferred).

2. Shift Lever Switch Open Faults - The loss of a shift lever switch contact when leaving

NEUTRAL, 1F, 1R, 2F, or 2R will result in NEUTRAL. Loss of a shift lever switch contact when

in 3F or higher or 3R or higher will result in remaining in the present gear. If either the Redundant

Neutral or Neutral switch is lost, the transmission will be neutralized whenever another switch

contact is lost.

3. Shift Lever Switch Short Active Faults - Two active speed switches will result in the

transmission remaining in the present gear until a valid speed signal is detected or NEUTRAL is

requested. If the forward or reverse switches are active, then the transmission will be neutralized

until a valid directional signal is determined.

4. Loss of or Erratic Transmission Output Speed (TOS) Signal - Loss of or erratic TOS will only

result in the EMS lamp and horn being turned ON to alert the operator that further operation of the

machine could cause damage. The overspeed feature will not function since the TOS will always

be 0 rpm.


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Lab F: Transmission Pressure Tests

Shop Lab Exercise

Procedure:

Fill out the worksheet.

Perform the following tests listed in the Power Train Systems Operation,

Testing and Adjusting Service Manual Module for the lab machine used:

• Supply Pressure

• Lubrication Pressure

• Pilot Pressure

• Clutch Pressures

• Differential Lock Pressure

Class Notes

Lab F Worksheet

Mechanic’s tools

The following test equipment:

1 - 1U5481 Pressure Gauge Group

1 - 1U5482 Pressure Adapter Group


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BACKGROUND

INFORMATION

INDIVIDUAL EXERCISE

MATERIALS NEEDED


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SPEED A-3 B-1 C-2 D-8 E-4 F-6 G-5 H-7

PARK • •

NEUTRAL • •

1-F • • •

2-F • • •

3-F • • •

4-F • • •

5-F • • •

6-F • • •

7-F • • •

8-F • • •

1-R • • •

2-R • • •

3-R • • •

4-R • • •

5-R • • •

6-R • • •

CLUTCH

PSI ± ± ± ± ± ± ± ±

LUBE IN NEUTRAL

LOW IDLE ( ± PSI) AT HIGH IDLE ( ± PSI)

LUBE IN FIRST FORWARD


PUMP IN NEUTRAL


PILOT PRESSURE


DIFFERENTIAL LOCK PRESSURE

Lab F: Transmission Pressure Tests Worksheet

SOLENOIDS ENERGIZED / CLUTCHES ENGAGED


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Transmission Case Study

Students may use service manual modules and their class notes to

complete the case study.

While grading a county road, the operator noticed that the transmission

would not allow the machine to move in third speed forward. The

operator also tried both first and second forward, but neither would move

the machine. The EMS indicated a Category 2 problem in the

transmission system. The Operation and Maintenance Manual stated that

the machine should be stopped and the cause should be investigated.

The operator called back to the shop to tell his supervisor of the problem

and wanted to know what to do. The supervisor called the Caterpillar

dealer for assistance. The field dispatcher did not have anyone available

immediately, but wanted to talk to the operator and give him a couple of suggestions.

What is the first step that should be performed in a logical troubleshooting

procedure?

What components or faults in the system could cause this problem?


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DIRECTIONS

SITUATION

QUESTIONS


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TRANSMISSION HYDRAULICSYSTEM POSTTEST

Directions: Modified True/False. If a statement is false, underline the word or words that make the

statement incorrect and replace the word(s) to make the statement correct.

transmission

Example: F 1. This is a hydraulic systems class.


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1. The motor grader engages two clutches for each speed.

2. The differential housing is used as the main oil sump.

3. The priority reducing valve limits the main system pressure to the clutches.

4. The drive shaft connects the parking brake to the differential.

5. The transmission pump supplies oil to the centershift lock group.

6. The parking brake is released by hydraulic oil from the transmission pump.

7. To change a clutch pressure, the modulation reduction valve initial pressure screw is

adjusted.

8. The manual modulation valve is also called the inching valve.

9. The pump is mounted directly on the engine.

10. The scavenge section of the pump is used to scavenge oil from the transmission housing.


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TRANSMISSION ELECTRICALSYSTEM POSTTEST

Directions: Complete the statement on the left with the word(s) on the right. Write the correct number

in the blank.


7/95

Selects the speeds and directions

Controls each shift

Disengages the transmission

Is used to display the ECM flash codes

Provides the ECM with ground speed

When the ______________ connector is uncoupled,

the ECM goes into the diagnostics mode.

The ______________ code is unique to each model

of motor grader.

Each clutch solenoid is connected to the harness by

a ______________ connector.

The ______________ is located on the shift console.

The clutch pressure switch is normally____________.

The ______________ wires of all the solenoids are

connected.

1. manual modulation valve

2. transmission indicator lamp

3. transmission speed sender

4. diagnostic

5. Sure-Seal

6. service tool connector

7. configuration

8. open

9. ECM

10. return

11. transmission shift lever

12. compensator valve

13. Deutsch

14. closed


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23

1

4

7

5

6

1.

2.

3.

4.

5.

6.

7.


Directions: Write the name of the component in the blank under each photo.


7/95

8

9

8.

9.


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SEEV2613 -34 - Student Materials

7/95

11

10 13

12

14. \

10.

11.

12.

13.

15. \

16. \

14

16

15


Directions: Write the name of the component in the blank under each photo.


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DIAGNOSTICS:

The temperature of the system oil is too hot.

Transmission speed signal is incorrect.

Motor grader "creeps" with the inching pedal fully

depressed.

Transmission does not shift into any gears forward or

reverse.

Transmission will not shift into reverse.

When testing the transmission pressures on the machine,

the __________ must be removed.

Preferred method of diagnosing a problem with the

transmission system.

If a transmission ECM is replaced, the ______________

must be entered.

This group can be removed without removing the

transmission.

To activate the diagnostic program within the ECM, the

______________.


7/95


Directions: Read the statement on the left and select the correct answer from the right and place the

letter in the blank.

A. diagnostic connector must be

uncoupled

B. transmission speed sender

output low

C. parking brake

D. loss of pilot pressure

E. ECAP

F. drive shaft

G. cooler bypass open

H. transmission configurationcode

I. inching pedal is out of

adjustment

J. solenoid A is defective

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