The document provides technical information on the operational principles and components of an excavator. It includes specifications, dimensions, and diagrams of the main components such as the engine, hydraulic devices, electrical equipment, cylinders, and control systems. The document is organized into sections covering general specifications and component layout, and sections on specific systems like the control, hydraulic, and electrical systems. Conversion tables are provided for common units like pressure, volume, temperature and other measurements.

1. FIAT KOBELCO CONSTRUCTION MACHINERY S.p.A. - ENGINEERING -
FORM No. 604.13.221 Edition - July 2002
EXCAVATOR
TECHNICAL MANUAL
OPERATIONAL PRINCIPLE
(Tier 2)
All information, illustrations and specifications in this manual are based on the latest product information available
at the time of publication.
The right is reserved to make changes at any time without notice.

2. IN-2 EX455
INTRODUCTION
To To
Quantity convert Into Multiply by Quantity convert Into Multiply by
from (SI) (Others) from (SI) (Others)
Lenght mm in 0.039 37 Pressure MPa kgf/cm2
10.197
mm ft 0.003 281 MPa psi 145.0
L US gal 0.264 2 Power kW CV-PS 1.360
Volume L US qt 1.057 kW HP 1.341
m3
yd3
1.308 Temperature °C °F °C x 1.8 + 32
Mass kg lb 2.205 Velocity km/h mph 0.621 4
Force N kgf 0.101 97 min-1
rpm 1.0
N lbf 0.224 8 Flow rate L/min US gpm 0.264 2
Torque N.m kgf.m 0.10197 mL/rev cc/rev 1.0
N.m lbf.ft 0.737 5
PAGE NUMBER
• Each page has a number, located on the external upper corner of the page. Each page number contains the
followinginformation:
Example: T 1-2-3
Consecutive page number for each group
Group number (if exist)
Sectionnumber
T : TechnicalManual
W : WorkshopManual
SYMBOLS
In this manual, the following safety alert symbol and signal words are used to alert the reader to the potential for
personal injury or machine damage.
This is the safety alert symbol.
When you see this symbol, be alert to the potential for personal injury.
Never fail to follow the safety instructions prescribed along with the safety alert symbol.
The safety alert symbol is also used to draw attentio in to component/part weights.
To avoid injury and damage, be sure to use appropriate lifting techniques and equipment when lifting heavy
parts.
UNITS USED
SI Units (International System of Units) are used in this manual.
MKSA system units and English units are also indicated in parentheses just behinds SI units.
Example: 24.5 MPa (250 kgf/cm2
, 3560 psi)
A table for conversion from SI units to other system units is shown below for reference purposes.

3. Section 3 - COMPONENT OPERATION
Group 1 Pump Device
Group 2 Swing Device
Group 3 Control Valve
Group 4 Pilot Valve
Group 5 Travel Device
Group 6 Other Components (Upperstructure)
Group 7 Other Components (Undercarriage)
TECHNICAL MANUAL EX455
OPERATIONAL PRINCIPLE
SECTION AND GROUP CONTENTS
Section 1 - GENERAL
Group 1 Specifications
Group 2 Component Layout
Section 2 - SYSTEM
Group 1 Control System
Group 2 Hydraulic System
Group 3 Electrical System

4. SECTION 1 EX455
GENERAL
CONTENTS
Group 1 - Specifications
Excavator Dimensions
(LCH version) ....................................... T1-1-1
Excavator Dimensions
(BEH version) ...................................... T1-1-2
Excavator Performance ........................ T1-1-3
Engine ................................................. T1-1-3
Engine Accessory................................ T1-1-4
Hydraulic Devices ................................ T1-1-4
Electrical Equipment ............................ T1-1-5
Group 2 - Component Layout
Main Components ................................ T1-2-1
Electrical System (1)
(Overall system) .................................. T1-2-2
Electrical System (2)
(Monitor and Switch panels) ................. T1-2-3
Electrical System (3)
(Relays, Diodes, etc) ........................... T1-2-4
Electrical System (4)
(Relays, Batteries, Fuses) ................... T1-2-6
Electrical System (5) (Fuses)............... T1-2-7
Other Components ............................... T1-2-8

5. SPECIFICATIONS
EX455 T1-1-1
EXCAVATOR DIMENSIONS
(LCH version)
OM0873
DIGGING DATA
OM0872
N-Track shoe width (mm) 600 700 800 900
O-Maximumwidth(reducedfortransport) (mm) 2 890 2 990 3 090 3 190
O*-Maximum width (in work condition) (mm) 3 390 3 490 3 590 3 690
Workingweight (kg) 46000 46500 47000 47500
Spec. Ground Pressure (bar) 0.83 0.72 0.64 0.57
With arm:
(1) 2 900 mm
(2) 3 400 mm
(3) 3 900 mm
(v
) 7 000 mm Boom
(*) Rear swing radius
VERSION A B C D D'(*) E F G H I L M
(1) 11 980 (1) 3 560
EX455LCH(vvvvv
) 4 470 5 470 1 380 3 580 3 600 (2) 11 870 (2) 3 430 3 330 3 000 3 285 1 190 770
(3) 11 880 (3) 3 440(mm)
Arm Arm Arm
2 900 mm 3 400 mm 3 900 mm
A 11390 12050 12430
A' 11140 11820 12200
B 7 270 7 730 8 190
B' 7 060 7 580 8 050
C 10040 10990 11060
D 6 890 7 630 7 760
E 5 060 4 980 4 920
(mm)
(mm)
(mm)
(mm)
(mm)
(mm)
(mm)

6. SPECIFICATIONS
T1-1-2 EX455
EXCAVATOR DIMENSIONS
(BEH version)
OM0875
DIGGING DATA
OM0874
(v
) 6 300 mm Boom
(*) Rear swing radius
VERSION A B C D D'(*) E F G H I L M
EX455BEH(vvvvv
) 4 470 5 470 1 380 3 580 3 600 11470 4 300 3 330 3 000 3 285 1 190 770
(mm)
N-Track shoe width (mm) 600 700 800 900
O-Maximum width (reduced for tranport) (mm) 2 890 2 990 3 090 3 190
O*-Maximum width (in work condition) (mm) 3 390 3 490 3 590 3 690
Workingweight (kg) 46500 47000 47500 48000
Spec. Ground Pressure (bar) 0.83 0.73 0.64 0.58
Arm
2 500 mm
A 10700
A' 10360
B 6 300
B' 6 150
C 9 800
D 6 900
E 4 950
(mm)
(mm)
(mm)
(mm)
(mm)
(mm)
(mm)

7. SPECIFICATIONS
EX455 T1-1-3
EXCAVATOR PERFORMANCE
GRADEABILITY ...........................................................................................................35° (70%) in continuous
TRAVEL SPEED
- Slow .................................................................................................................... 0 to 2.1 mph (0 to 3.4 km/h)
- Fast .....................................................................................................................0 to 3.4 mph (0 to 5.5 km/h)
ENGINE
MAIN SPECIFICATIONS
- Manufacturer .........................................................................................................................................ISUZU
- Model....................................................................................................................................AA-6WG1TQA-01
- Type .....................................................Diesel, 4 cycle, vertical, 6-cylinder inline, turbocharged, water-cooled,
direct injection type
- Cyl. No.-bore x stroke .......................................................................... 6-147 mm x 154 mm (5.78 in x 6.06 in)
- Piston displacement ......................................................................................................... 15 681 cm3
(957 in3
)
- Rated output ...................................................................................................................... 235 kW/1 800 min-1
- Compression ratio ......................................................................................................................................16.4
- Dry weight........................................................................................................................... 1 252 kg (2 760 lb)
- Firing order.......................................................................................................................................1-5-3-6-2-4
- Rotation direction ........................................................................................... Clockwise (facing fly wheel end)
COOLING SYSTEM
- Cooling fan............................................................................................... Dia. 850 mm, 6 blades, draw-in type
- Fan pulley ratio .................................................................................................................... Engine rpm x 0.89
- Thermostat (under atmospheric pressure) .......................................................Cracking temp. : 82 °C (180 °F)
Full open temp. : 95 °C (203 °F)
- Water pump ...........................................................................................................Centrifugal type, belt driven
LUBRICATION SYSTEM
- Lubrication pump type ....................................................................................................................Gear pump
- Oil filter ............................................................................... Full-flow paper element type with bypass function
- Oil cooler ........................................................................................................................ Water-cooled, built-in
STARTING SYSTEM
Motor ............................................................................................ Magnetic pinion shift system, reduction type
Voltage-Output ................................................................................................................................... 24 V-7 kW
PRE-HEAT SYSTEM
- Heating method ...........................................................................................Intake heater with magnetic valve
ENGINE STOP SYSTEM
- Stop method ......................................................... Fuel cut (Employs both key switch and engine stop motor)
ALTERNATOR
- Type ........................................................................................................................... AC type (with regulator)
-Voltage-Output ...................................................................................................... 24 V-50 A (Brush-less type)
SUPERCHARGING SYSTEM
- Type ............................................................................................................... Exhaust-gas-turbo type RHC 92
FUEL SYSTEM
- Injection pump model .......................................................................................................Bosch type P-Model
- Governor ............................................................................................... Centrifugal all speed control EP/RSV
- Injection nozzle....................................................................................................................... Multihole nozzle

8. SPECIFICATIONS
T1-1-4 EX455
ENGINE ACCESSORY
RADIATOR ASSEMBLY
- Type .............................................................................................Radiator/Oil Cooler tandem type assembly
- Weight ..................................................................................................................................... 260 kg (573 lb)
- RadiatorCapacity......................................................................................................................................21 L
- Oil Cooler Capacity ...................................................................................................................................16 L
BATTERY
- Capacity ........................................................................................................................................ 180 Ah x 2
- Voltage .............................................................................................................................................. 12 V x 2
HYDRAULIC DEVICES
MAIN PUMP
- Model ...........................................................................................................................................K5V200DPH
- Type ................................................................. Variable displacement plunger pump: regulator attached type
- Max. flow (Theoretical value) ..................................................................................................... 360 L/min x 2
PILOT PUMP
- Model .................................................................................................................................... HY/ZFS 11/16.8
- Type ....................................................................................................... Fixed displacement type gear pump
- Max. flow (Theoretical value) .......................................................................................................... 33.6 L/min
CONTROLVALVE
- Model ............................................................................................................................................... UH36-52
- Type ................................................................................................................... Pilot pressure operated type
(4-spool + 5-spool)
- Main relief pressure ................................................................... Normal: 29.4 MPa (300 kgf/cm2
) at 80 L/min
Power Boost (Travel): 34.3 MPa (350 kgf/cm2
) at 200 L/min
- Overload relief pressure ..................................... (Boom, Arm, Bucket): 30.9 MPa (315 kgf/cm2
) at 110 L/min
Swing: 26.5 MPa (270 kgf/cm2
) at 160 L/min
SWING DEVICE
- Type ........................................................................................................ Two-stage planetary reduction type
- Reduction ratio ........................................................................................................................................ 16.2
- Weight .....................................................................................................................................278 kg (617 lb)
SWING MOTOR
- Model ..................................................................................................................... M2X150CAB-10A-06/250
- Type ..............................................................................Swash-plate type, fixed-displacement plunger motor
- Displacement.............................................................................................................................148.5 cm3
/rev
SWING BRAKE VALVE
- Type ...............................................................................................................Non counterbalance valve type
- Relief pressure ........................................................................................ 24.5 MPa (250 kgf/cm2
) at 90 L/min
SWING PARKING BRAKE
- Type ..............................................................................................................Multiple-wet-plate negative type
- Cracking pressure for release .......................................................................................... 2 MPa (20 kgf/cm2
)
TRAVEL DEVICE
- Type ..................................................................................................... Three-stage planetary reduction gear
- Reduction gear ratio ............................................................................................................................ 55.318
- Weight ..................................................................................................................................................560 kg
TRAVEL MOTOR
- Model ..................................................................................................................................... MSF340VP-CB
- Type ......................................................................... Swash-plate type, variable displacement plunger motor
- Displacement (Theoretical value) ......................................................... Fast speed: 175.7 cm3
(10.7 in3
) /rev.
Slow speed: 271.5 cm3
(16.6 in3
) /rev.
TRAVEL BRAKE VALVE
- Type .................................................................................................................... Counter balance valve type
- Relief pressure .......................................................................................................... 36.8 MPa (375 kgf/cm2
)
TRAVEL PARKING BRAKE
- Type ..............................................................................................................Multiple-wet-plate negative type
- Brake release cracking pressure ................................................................................. 1.67 MPa (17 kgf/cm2
)

9. SPECIFICATIONS
EX455 T1-1-5
Boom Arm Bucket
Roddiameter 115 mm 130 mm 120 mm
Cylinderinnerdiameter 170 mm 190 mm 170 mm
Stroke 1 590 mm 1 940 mm 1 321 mm
Fully retracted length 2 260 mm 2 710 mm 2 041 mm
CYLINDERS
ACCUMULATOR
- Model .............................................................................................................................................MU70-300
- Type ........................................................................................................... Nitrogen gas sealed bladder type
- Capacity ............................................................................................................................ 300 cm3
(18.3 in 3
)
- Gas charging pressure ..................................................................................... 2.4 MPa (24 kgf/cm2
, 341 psi)
PILOT SHUT-OFF VALVE
- Model .................................................................................................................................................... RC50
- Type ............................................................................................................................................. Rotary type
SHOCKLESS VALVE (Front functions)
- Model ........................................................................................................................................... VUP149J/0
- Type ............................................................................................................. 4 valve block flow regulator type
SHOCKLESS VALVE (Travel function)
- Type ............................................................................................................. 4 valve block flow regulator type
3-SPOOL SOLENOID VALVE UNIT
- Application ....................................................................................................SA: Main relief pressure shift
SB: Travel speed mode shift
SC: Swing parking brake release
- Pilot relief pressure ........................................................................................... 3.9 MPa (40 kgf/cm2
, 569 psi)
at 13 Liters (3.4 US gal)/min
FRONT ATTACHMENT PILOT VALVE
- Model ................................................................................................................................. HVP04D-040-101
TRAVEL PILOT VALVE ..........................................................................................................HVP04A-040-101
OIL COOLER BYPASS CHECK VALVE
- Crackingpressure ....................................................................................... 340 kPa (3.5 kgf/cm2
) at 40 L/min
ELECTRICAL EQUIPMENT
BATTERY RELAY
- Voltage-Current .......................................................................................................................... 24 V - 100 A
STARTER RELAY
- Voltage .................................................................................................................................................... 24 V
HORN
- Specifications ................................................................................................................. 24 V - 1.5 A, 113 dB
LIGHT
- Specifications ............................................................................................Work lights: Halogen 24 V - 70 W
Dome light: 24 V - 10 W
AIR CONDITIONER
- Refrigerant............................................................................................................................................. 134 a
- Temperature control ............................................................................................................ Electronic control

10. SPECIFICATIONS
T1-1-6 EX455
NOTES

11. COMPONENT LAYOUT
EX455 T1-2-1
MAIN COMPONENTS
1 - Bucket Cylinder
2 - Arm
3 - Arm Cylinder
4 - Boom
5 - Boom Cylinder
6 - Front/Swing Pilot Valve
7 - Swing Bearing
8 - Center Joint
9 - Swing Device
10 - Fuel Tank
11 - Control Valve
12 - Engine
13 - Radiator
14 - Oil Cooler
15 - Counterweight
16 - Fuel Filters
17 - Engine Oil Filters
18 - Muffler
19 - 3 Spool Solenoid Valve Unit
20 - Pump Device
21 - Pilot Filter
22 - Hydraulic Oil Tank
23 - Travel Device
24 - Shockless Valve (Travel)
25 - Upper Roller
26 - Swing Shuttle Valve
27 - Shockless Valve (Front)
28 - Lower Roller
29 - Travel Shuttle Valve
30 - Pilot Shut-Off Valve
31 - Track Adjuster
32 - Front Idler
33 - Air Filter
34 - Travel Pilot Valve
35 - Bucket
32
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
34
35
2
1
33
SM5701

12. COMPONENT LAYOUT
T1-2-2 EX455
ELECTRICAL SYSTEM (1)
(Overall system)
1 - Work Light (On Boom)
2 - Monitor
3 - Pressure Switch (Travel)
4 - Horn
5 - Work Light
6 - Fuel Sensor with Fuel Low Level Switch
7 - Battery
8 - DP Sensor (4-Spool Side)
9 - Air Filter Restriction Switch
10 - Overheat Switch L
11 - Coolant Temperature Sensor (For Monitor)
12 - Overheat Switch H
13 - Alternator
14 - Engine Oil Level Switch
15 - Engine Oil Pressure Switch
16 - N (Engine Speed) Sensor
17 - Starter
18 - EC Motor
19 - Coolant Level Switch
20 - DP Sensor (5-Spool Side)
21 - 3-Spool Solenoid Valve Unit
22 - Hydraulic Oil Level Switch
23 - Hydraulic Oil Temperature Switch
24 - Pressure Switch (Other)
25 - Pressure Switch (Swing)
26 - Pressure Switch (Arm Roll-In)
27 - Pressure Switch (Boom Raise)
28 - Windshield Washer Motor
29 - Fuse Box
30 - Wiper Box
31 - Wiper Motor
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
19
20
21
22
23
24
25
26
27
28
29
31
SM5735
30
18

13. COMPONENT LAYOUT
EX455 T1-2-3
ELECTRICAL SYSTEM (2)
(Monitor and Switch panels)
1 - Monitor Panel
2 - Switch Panel
3 - Cigar Lighter
4 - Provision for Hydraulic Breaker Control Switch
5 - Provision for Nordic Kit Control Switch
6 - Provision for Rotary Bucket Control Switch
7 - Provision for Load Momentum Alarm Control Switch
8 - Provision for further option Control Switch
9 - Air Conditioner Control Panel
10 - Engine Control Dial
11 - E Mode Switch
12 - SP Mode Switch
13 - Key Switch
14 - Power Boost Switch
15 - Warm Up Complete Indicator
16 - Coolant Temperature Gauge
17 - Fuel Gauge
18 - SP Mode Indicator
19 - E Mode Indicator
20 - Auto-Idle Indicator
21 - Hydraulic Oil Level Indicator
22 - Preheat Indicator
23 - Air Filter Restriction Indicator
24 - Fuel Level Indicator
25 - Attachment Mode Indicator
26 - Precision Mode Indicator
27 - Trenching Mode Indicator
28 - General Purpose Mode Indicator
29 - Work Mode Switch
30 - Buzzer Stop Switch
31 - Travel Mode Switch
32 - Auto-Idle Switch
33 - Wiper Switch
34 - Washer Switch
35 - Work Light Switch
36 - Level Check Switch
37 - Hydraulic Breaker filter clogging Indicator (opt)
38 - Overheat Indicator
39 - Engine Oil Pressure Indicator
40 - Alternator Indicator
41 - Engine Oil Level Indicator
42 - Coolant Level Indicator
1
2
3
4
5
6
7
8
14
13
12
11
10
9
SM6501
15 16 17
18
19
20
21
22
23
24
25
26
27
28
29
30
32 31
42
41
40
39
38
37
36
35
34
33

14. COMPONENT LAYOUT
T1-2-4 EX455
ELECTRICAL SYSTEM (3)
(Relays, Diodes, etc.)
Cab compartment
SM5702
Detail F
View D
View E
View B
View C
View A
11 - EC controller
12 - PVC controller
13 - Air conditioner relays (if installed)
14 - Q.O.S. Controller
15 - Relay box
16 - Load momentum alarm buzzer provision
17 - Load momentum alarm relay provision (R1)
18 - R.H. Rotation bucket relay provision (R3)
19 - L.H. Rotation bucket relay provision (R4)
10 - Cab light relay (R5)
11 - Rear Cab light relay (R6)
12 - EC Motor relay (R7)
13 - Diodes 1-2
14 - Diodes 3-4-5
15 - A-B-C junction connector
16 - D-E-F junction connector
17 - G-H-I junction connector
18 - J-K-L junction connector
19 - Dr. EX connector
20 - Fuse box
20
4
5
C
12
13
14
6
7
8
9
10
11
➮
➮D
B
➮E
➮A
➮
15
16
17
18
3
2
1
F
19

15. COMPONENT LAYOUT
EX455 T1-2-5
SM5604
3
4
5
6
78
1 2
1 - Connectors for monitor and switch panels
2 - Cigarette lighter
3 - Connectors to cab harness
4 - Connectors not used
5 - Windshield wiper controller
ELECTRICAL SYSTEM (3)
(Relays, Diodes, etc)
6 - (1) connector for breaker switch
(2) connector for cab light switch
(3) connector for bucket rotation
(4) connector for load momentum alarm switch
(5) connector for rear cab light
7 - Connector not used
8 - Wiper motor connector
Cab side

16. COMPONENT LAYOUT
T1-2-6 EX455
ELECTRICAL SYSTEM (4)
(Relays, Batteries, Fuses)
1 - Fuse Link 1 (50A)
2 - Fuse Link 2 (40A)
3 - Fuse Link 3 (80A)
4 - Starter relay
5 - Battery relay
6 - Battery
7 - Glow relay
8 - Connection box
SM5703
1 3
2
4
5
8
7
6
5

17. COMPONENT LAYOUT
EX455 T1-2-7
Fuses in the tool kit and batteries compartment
ELECTRICAL SYSTEM (5)
(Fuses)
Fuses in the fuse box
8 6 4 35 2 179
19 1820 1617 14 1315 12 11
10
OM0231
OM0232
SM5704
Fuse link (1), (2) and (3)
FUSES IN THE BOX
Fuse
LABEL
PROTECTED Rating
No. CIRCUIT (A)
1 SW. BACK UP
Back-up
5power
Mainpower
2 ENG. C/U supply for 10
ECController
3 E.C. MOTOR Ec Motor 10
4 AUXILIARY
Auxiliary
5powersupply
5
REAR CAB Rear Cab light
10(LIGHT) powersupply
6 LUBRICATOR
Lubricator
10powersupply
ROTARY
Rotary bucket
7
BUCKET
solenoid valve 10
powersupply
8 SOLENOID
Solenoid valve
5powersupply
Switch box
59 SW. BOX powersupply
10
HEATING Operator'sheating
10SEAT seat power supply
11 WIPER Wiper 10
12 HEATER
Heater
20powersupply
13 LIGHT
Work light
15powersupply
14 CAB LIGHT
Cab light
10powersupply
15 RADIO
Radio
5powersupply
16 LIGHTER Lighter
15powersupply
17 HORN Hornes 10
18 GLOWRELAY
Glowrelay
5powersupply
19 POWERON
Power on signal
5from key switch
20 AIRCOND. Airconditioning 10
FUSES IN THE TOOL KIT AND BATTERIES
COMPARTMENT
– FUSE (1)
Batteries
50powersupply
– FUSE (2)
Glowplug
40powersupply
– FUSE (3)
Mainpower
80supply with key

18. COMPONENT LAYOUT
T1-2-8 EX455
OTHER COMPONENTS
Pump Device
1 - Main pump 1 (front)
2 - Pilot pump
3 - Main pump 2 (rear)
4 - Pump 1 A sensor (Pump Displacement Sensor)
5 - Pump 1 delivery pressure sensor (P sensor)
6 - Pump 2 delivery pressure sensor (P sensor)
7 - Pump Control Proportional Solenoid valve 1
8 - Pump Control Proportional Solenoid valve 2
9 - Pump 2 A Sensor (Pump Displacement Sensor)
3
2
4
1
65
➮
A
SM5706
View A
9
6
8
5
74

19. COMPONENT LAYOUT
EX455 T1-2-9
Control valve
SM6509
Make-Up Valve
Holding Valve (Boom)
Overload Relief Valve
5-Spool Block
Pump Control Valve
(5-Spool Block Side)
DP Sensor
(5-Spool Block Side)
Shuttle Valve
Flow Combiner
Valve 4-Spool Block
Main Relief Valve
Front Side
SM6508
Travel (L)
Auxiliary
Boom 2
Arm 1
Swing
Overload Relief
Valve
Make-Up Valve
Holding Valve (Arm)
Overload Relief Valve
5-Spool
Block
Tank Port
T1
Tank Port
T2
4-Spool
Block
Pump Control Valve
(4-Spool Block Side)
Arm Regenerative
Valve
DP Sensor
(4-Spool Block Side)
Arm 2
Boom 1
Bucket
Front Side
Travel (R)

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21. COMPONENT LAYOUT
T1-2-10 EX455
Swing Device
SM6505
SM6506
1
3
2
Travel Device
3-Spool Solenoid Valve Unit
SM6507
4 5 6 7
1 - Swing Relief Valve
2 - Counterbalance Valve
3 - Travel Relief Valve
4 - Swing Parking Brake Release Solenoid Valve (SC)
5 - Travel Mode Shift Solenoid Valve (SB)
6 - Main Relief Pressure Shift Solenoid Valve (SA)
7 - Pilot Relief Valve

22. SECTION 2 EX455
SYSTEM
CONTENTS
Group 1 - Control System
Outline ....................................................T2-1-1
Engine Control ........................................ T2-1-2
Pump Control .......................................... T2-1-6
Valve Control ........................................ T2-1-14
Other Control ........................................ T2-1-19
Group 2 - Hydraulic System
Outline ................................................. T2-2-1
Main Circuit.......................................... T2-2-2
Pilot Circuit .......................................... T2-2-7
Group 3 - Electrical System
Outline ................................................... T2-3-1
Power Circuit .......................................... T2-3-2
Bulb Check Circuit ................................. T2-3-4
Accessory Circuit .................................. T2-3-6
Preheat Circuit ....................................... T2-3-8
Engine Start Circuit............................. T2-3-10
Charging Circuit .................................. T2-3-12
Surge Voltage Prevention Circuit ......... T2-3-14
Engine Stop Circuit ............................. T2-3-16