SENR6236
May 1994
311 & 312 Excavators
Electrical System
9LJ262-UP
6GK393-UP
2KM111-UP
Connector Location
Connector
Machine
Location
Harness And/Or
Component
Schematic
Location
Connector
Machine
Location
Harness And/Or
Component
Schematic
Location
40 Contacts
CONN1
*
A - 1060029
Controller
D-12
CONN12
C - 7Y8139
F - 518216
C-6
24 Contacts
CONN2
*
A - 1060029
Controller
F-12
CONN30
A
E - 1114712
Monitor
E-2
CONN9
D
A - 1060029
B - 1059920
D-11
CONN32
D - 5l8217
Wiper Motor
F-2
CONN8
D
A - 1060029
B - 1059920
D-10
CONN12
R - 7Y8105
F - 5l8216
C-7
CONN13
A
A - 1060029
F - 5l8216
C-5
CONN43
C - 7Y8139
Speaker
B-6
CONN24
A - 1060029
G - 7Y3922
D-3
CONN21
B
H - 4l5463
Lower Wiper Switch
C-3
CONN18
B
A - 1060029
H - 4l5463
D-4
CONN29
A - 7Y8105
Converter
B-7
CONN17
C
A - 1060029
K - 4l5411
E-5
CONN25
A - 1060029
G - 7Y3922
D-3
CONN3
D
A - 1060029
L - 1059958
E-9
CONN23
A - 1060029
J - 7Y3868
F-3
CONN5
D
A - 1060029
L - 1059958
F-9
CONN39
A - 1060029
Refrigerant Low Press Switch
D-12
CONN6
D
A - 1060029
L - 1059958
F-9
CONN45
A - 1060029
Travel Alarm
D-11
CONN4
D
B - 1059920
L - 1059958
E-9
CONN50
E
B - 1059920
Boom Raise Press Switch
B-8
9 Contacts
CONN57
C - 7Y8139
Radio
C-6
CONN49
B - 1059920
Fuel Level Sensor
B-6
7 Contacts
CONN14
A
A - 1060029
E - 1114712
C-5
CONN51
E
B - 1059920
Implement Swing Press Switch
C-8
CONN10
D
A - 1060029
B - 1059920
D-10
CONN53
F
8 - 1059920
Level Solenoid
A-8
CONN11
D
B - 1059920
Safety Relay
E-9
CONN38
B - 1059920
N - 4l5460
B-2
CONN28
D - 5l8217
F - 5l8216
E-2
CONN48
B - 1059920
PP 5l8358
A-6
CONN15
A - 1060029
Air Conditioner Unit
D-6
CON N56
F
B - 1059920
Proportional Reducing Valve
A-8
CONN19
B
A - 1060029
H - 415463
D-4
CONN41
B - 1059920
Refueling Pump
A-3
CONN15
A - 1060029
Heater Unit
E-6
CONN34
B - 1059920
Refueling Pump Switch
CONN44
B - 1059920
Governor Actuator
A-11
CONN42
B - 1059920
Speed Sensor
B-10
CONN27
B
G - 7Y3922
Engine Speed Dial
C-2
CONN52
E
B - 1059920
Travel Press Switch
C-8
CONN58
A - 1060029
A - 1060029
D-12
CONN55
F
B - 1059920
Travel Speed Solenoid
A-8
CONN33
A - 1060029
Lower Wiper Motor
F-2
CONN54
F
B - 1059920
Trenching Solenoid
A-8
Connector Location
Connector
Machine
Location
Harness And/Or
Component
Schematic
Location
Connector
Machine
Location
Harness And/Or
Component
Schematic
Location
CONN31
A
E - 1114712
Action Alarm
D-2
CONN20
C
J - 7Y3868
Horn Switch
F-3
CONN35
F - 5l8216
M - 7Y8245
F-1
CONN26
B
G - 7Y3922
Low Idle Switch
D-3
CONN22
B
H - 4l5463
Lower Washer Switch
B3
CONN7
A - 7Y8105
Converter
B-7 Plug No.
CONN37
B - 1059920
Air Conditioner Clutch
Solenoid
C-12
CONN5
D
Three
CONN36
F-5l8216
M - 7Y8245
E-1
CONN6
D
Two
CONN59
C
A - 1060029, S - 1060026
T - 1060027
E-5
CONN3
D
One
CONN60
C
S - 1060026
Radio Control Switch
E-4
CONN9
D
One
CONN8
D
Two
NOTE: Each of CONN 3, 5,6,8 and 9 located in area D has 10 poles with different
number of plugs, as shown below. The following chart will help you to identify
them.
4 Contacts
3 Contacts
2 Contacts
2 Contacts
Bullet
Terminal
Connecter No. In Area D
10 Contacts
6 Contacts
5 Contacts
4 Contacts
6
8
4
1
1
1
3
1
2
5
2
3
7
4
3
4
2
4
5
3
6
7
2
22
6
23
24
25
4
5
3
4
1
2
3
6
8
21
3
2
1
18
4
19
20
16
2
3
17
13
14
15
5
11
12
9
8
8
1
10
1
A
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
3
4
5
6
8
9
10
11
12
14
15
13
16
B
C
D
E
1
2
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
7
F
17
18
19
20
21
22
23
24
25
Machine Harness Connector And Component Locations
A
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
3
4
5
6
8
9
10
11
12
14
15
13
16
B
C
D
E
1
2
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
7
F
17
18
19
20
21
22
23
24
25
29
9
10
1
2
3
4
3
4
1
2
1
2
3
4
5
6
3
4
5
6
1
2
7
AREA A
AREA A
AREA B
AREA B
1
3
4
5
3
4
1
2
1
2
3
4
5
6
7
8
3
4
5
6
8
1
2
7
AREA C
AREA D
1
2
3
4
3
4
5
1
2
1
2
3
3
1
2
AREA E
AREA F
Component Location Chart
Machine
Location
Component
Schematic
Location
Machine
Location
Component
Schematic
Location
1
Actuator - Governor
A-12 9D
Relay - Safety
E-9
3A
Alarm - Action
D-2 21
Relay - Starter
B-12
2
Alarm - Travel
D-11 7D
Relay - Washer
E-8
3
Alternator
B-12 7D
Relay - Wiper
E-8
4
Antenna
C-6, 7 1C
Resistor - Backup
F-5
5
Battery
C-9 1F
Sender - Hydraulic Oil Temperature
A-8
1D
Block - Terminal
D-9 22
Sensor - Engine Coolant Temperature
B-12
4D
Breaker
D-9 23
Sensor - Fuel Level
B-5
6
Controller
F-12 24
Sensor - Speed
B-10
7
Converter
B-7 25
Solenoid - Air Conditioner Compress Clutch
C-12
3B
Dial - Engine Speed
C-2 26
Solenoid - Engine Shutdown
B-10
6D
Fuse - Block
F-7, 8, 9 5F
Solenoid - Level
A-8
8
Heater - Air
B-10 3F
Solenoid - Travel Speed
A-8
9
Horn
A-2, B-2 2F
Solenoid Trenching
A-8
10
Lamp - Boom
A-1, B-1 27
Speaker
B-6
11
Lamp - Cab
E-1, F-1 3E
Switch - Boom Raise Press
B-8
12
Lamp - Chassis
A-2 5D
Switch - Disconnect
D-9
13
Lamp - Dome
D-6 28
Switch - Engine Oil Press
B-12
1A
Lighter - Cigar
E-3 4B
Switch - Governor Backup
C-5
2A
Meter - Service
E-2 3C
Switch - Horn
F-3
4A
Monitor
E-2 1E
Switch - Implement Swing Press
C-8
14
Motor - Lower Washer
F-12 2B
Switch - Low Idle
D-3
15
Motor - Lower Wiper
F-2 6B
Switch - Lower Washer
B-3
16
Motor - Starter
A-12 7B
Switch - Lower Wiper
C-3
17
Motor - Washer
F-12 29
Switch - Neutral Start
F-2
18
Motor - Wiper
F-2 2C
Switch - Pump Backup
E-4
19
Pump - Refueling
A-3 4C
Switch - Radio Control
E-4
20
Radio
C-6 30
Switch - Refrigerant Low Press
D-12
7D
Relay - Boom Lamp
E-8 31
Switch - Refueling
A-5
7D
Relay - Chassis/Cab Lamp
E-8 32
Switch - Refueling Pump
A-3
2D
Relay - Engine Shutdown
D-7 5B
Switch - Speed Change
B-4
8D
Relay - Heater
D-8 1B
Switch - Starter
C-2
7D
Relay - Horn
E-7 2E
Switch - Travel Press
C-8
3D
Relay - Main
D-7 33
Unit - Air Conditioner
D-6
7D
Relay - Refueling Pump
E-7 34
Unit - Heater
E-6
4F
Valve - Proportional Reducing
A-8
T
Normally open switch that will close with an increase of a specific condition (temp-press-etc.).
Normally open switch that is closed due to an applied condition, and will open again with a
specific decrease in that condition.
Normally closed switch that will open with an increase of a specific condition.
Normally closed switch that is open due to an applied condition, and will close again
with a specific decrease in that condition.
The circle indicates that the component has screw terminals and a wire can be disconnected
from it.
No circle indicates that the wire cannot be disconnected from the component.
This indicates that the component has a wire connected to it that is connected to ground.
This indicates that the component does not have a wire connected to ground. It is grounded
by being fastened to the machine.
Electrical Schematic Symbols And Definitions
Pressure
Symbol
Temperature
Symbol
Level
Symbol
Flow
Symbol
A AA
2
A AA
1
2
325-PK-14
C
A
325-PK-14
200-BK-14
T
FUSE - A component in an electrical circuit that will open the circuit if too much current flows
through it.
REED SWITCH - A switch whose contacts are controlled by a magnet. A magnet closes the
contacts of a normally open reed switch; it opens the contacts of a normally closed reed switch.
SENDER - A component that is used with a temperature or pressure gauge. The sender
measures the temperature or pressure. Its resistance changes to give an indication to the
gauge of the temperature or pressure.
RELAY (Magnetic Switch) - A relay is an electrical component that is activated by electricity.
It has a coil that makes an electromagnet when current flows through it. The electromagnet
can open or close the switch part of the relay.
CIRCUIT BREAKER (C/B) - A component in an electrical circuit that will open the circuit if too
much current flows through it. This does not destroy the circuit breaker and it can be reset to
become part of the circuit again.
SOLENOID - A solenoid is an electrical component that is activated by electricity. It has a coil
that makes an electromagnet when current flows through it. The electromagnet can open or
close a valve or move a piece of metal that can do work.
Harness And Wire Electrical Schematic Symbols
Socket
Pin
Pin or Socket
Number
Wire, Cable, or Harness
Assembly Identification
Single Wire
Connector
Circuit Number
Identification
Wire
Gauge
Wire
Color
Plug
Receptacle
9X-1123
Component
Part Number
Electrical Schematic Symbols And Definitions
1
1
1
2
2
Typical representation of a
Sure-Seal connector. The
plugand receptacle contain
both pins and sockets.
Typical representation of a
Deutsch connector. The
plug contains all sockets
and the receptacle contains
all pins.
MAGNETIC LATCH SOLENOID - A magnetic latch solenoid is an electrical component that is
activated by electricity and held latch by a permanent magnet. It has two coils (latch and unlatch)
that make electromagnet when current flows through them. It also has an internal switch that places
the latch coil circuit open at the time the coil latches.
©
1994 Caterpillar
All Rights Reserved
Printed in U.S.A.
A-3
101112
10
11
B731-WH
B730-OR
105-YL
122-BU
200-BK
122-BU
120-YL
122-BU
120-YL
RADIO (NOTE D)
1
2
210-BK
135-BU
200-BK
200-BK
2
200-BK
4
1
3
365-YL
325-PK
200-BK
323-WH
200-BK
607-PK
616-BU
322-GY
200-BK
235-BK
200-BK
200-BK
607-PK
200-BK
323-WH
200-BK
365-YL
325-PK
200-BK
113-OR
B751-YL
513-OR
306-GN
A763-GY
A768-BU
A769-GY
309-GY
403-GN
323-WH
365-YL
327-PK-10
101-RD-4
109-OR-6
616-BU
877-YL-4
607-PK
142-BU-14
200-BK
330-YL
D746-PK
309-GY
403-GN
D746-PK
309-GY
403-GN
403-GN
309-GY
A769-GY
A768-BU
A763-GY
306-GN
513-OR
B751-YL
D764-GN
B965-GY
B964-YL
B737-GN
A771-PU
113-OR
D746-PK
A762-PU
A761-PU
788-YL
763-BU
495-GN
492-GY
BK-00200-BK
200-BK
267-BK
235-BK
235-BK
308-YL
310-PU
105-BR
120-YL
185-YL-14
129-BU
124-GN-14
320-OR
500-BR
501-GN
103-YL
118-GY
152-BU
615-YL
113-OR
A768-BU
B731-WH
B730-OR
B740-OR
B739-WH
B790-OR
B789-BR
B955-YL
B956-PK
B786-BU
A755-PK
A756-BU
A757-GY
A758-BR
410-WH
308-YL
578-BU
519-PK
513-OR
513-OR
519-PK
578-BU
308-YL
410-WH
A758-BR
A757-GY
A756-BU
A755-PK
B786-BU
B956-PK
B955-YL
B789-BR
B790-OR
B739-WH
B740-OR
B730-OR
B731-WH
A768-BU
235-BK
235-BK
267-BK
200-BK
200-BK
D764-GN
D746-PK
A762-PU
788-YL
405-GY
492-GY
A761-PU
495-GN
763-BU
B964-YL
B965-GY
B737-GN
A771-PU
491-PK
506-PU
332-BU
786-GN
121-YL
791-PK
792-OR
A983-BU
184-BU
877-YL
519-PK
513-OR
321-BR
121-YL
121-YL
321-BR
513-OR
519-PK
321-BR
121-YL
519-PK
513-OR
235-BK
267-BK
786-GN
308-YL
410-WH
A758-BR
A757-GY
A756-BU
A755-PK
B786-BU
B956-PK
B955-YL
B789-BR
B790-OR
B739-WH
B740-OR
B730-OR
B731-WH
A768-BU
877-YL
184-BU
A983-BU
792-OR
791-PK
491-PK
A771-PU
B737-GN
B965-GY
B964-YL
763-BU
495-GN
491-PK
405-GY
124-GN-14
519-PK
615-YL
103-YL
200-BK-14
200-BK
578-BU
200-BK
200-BK
506-PU
332-BU
321-BR
D764-GN
D746-PK
A762-PU
788-YL
405-GY
492-GY
A761-PU
495-GN
791-PK
792-OR
A983-BU
184-BU
877-YL
A768-BU
B731-WH
B730-OR
B740-OR
B739-WH
B790-OR
B789-BR
B955-YL
267-BK267-BK
266-BK
265-BK
264-BK
235-BK
763-BU
B956-PK
B964-YL
B786-BU
B965-GY
B737-GN
A771-PU
491-PK
A755-PK
A756-BU
A757-GY
A758-BR
410-WH
308-YL
786-GN
235-BK
RD-00
RD-00
235-BK
513-OR
D746-PK
109-OR-6
403-GN
309-GY
200-BK-6
492-GY
405-GY
306-GN
330-YL
101-RD-4
101-RD-4
330-YL
306-GN
405-GY
492-GY
200-BK-6
309-GY
403-GN
109-OR-6
D746-PK
513-OR
877-YL-4
A762-PU
788-YL
327-PK-10
200-BK
200-BK
200-BK
200-BK-6
113-OR
200-BK
A761-PU
A763-GY
B751-YL
RD-00
RD-00
101-RD-4
330-YL
306-GN
405-GY
492-GY
200-BK
200-BK
200-BK-6
309-GY
403-GN
109-OR-6
D746-PK
200-BK
200-BK
513-OR
B751-YL
A763-GY
A761-PU
200-BK
113-OR
200-BK-6
200-BK
200-BK
200-BK
200-BK-10
200-BK-10
327-PK-10
327-PK-10
788-YL
A762-PU
877-YL-4
877-YL-4
B737-GN
D764-GN
200-BK
A771-PU
491-PK
B964-YL
B965-GY
763-BU
A768-BU
A769-GY
101-RD-14
112-PU-14
112-PU-14
112-PU-14
310-PU
308-YL
320-OR
152-BU
103-YL
152-BU
118-GY
121-YL
184-BU
103-YL
114-GN
120-YL
113-OR
500-BR
118-GY
501-GN
615-YL
BK-00
149-PU
120-YL
113-OR
115-PK
142-BU-14
615-YL
501-GN
118-GY
500-BR
113-OR
184-BU
786-GN
332-BU
506-PU
121-YL
792-OR
791-PK
A983-BU
877-YL
616-BU
607-PK
323-WH
365-YL
322-GY
101-RD-14
112-PU-14
112-PU-14
112-PU-14
112-PU-14
112-PU-14
332-BU
200-BK
200-BK
BK-00
BK-00
101-RD-4
310-PU
877-YL
877-YL-4
327-PK-10
109-OR-10
109-OR-6
200-BK
112-PU-14
112-PU-14
112-PU-14
112-PU-14
BK
RD
877-YL
A983-BU
791-PK
792-OR
121-YL
506-PU
332-BU
786-GN
184-BU
113-OR
615-YL
152-BU
118-GY
103-YL
501-GN
500-BR
320-OR
124-GN-14
129-BU
185-YL-14
D746-PK
D746-PK
200-BK
330-YL
309-GY
309-GY
403-GN
403-GN
WH/YL
BK
WH/BU
YL
WH/GN
101-RD-6
101-RD-14
101-RD-14
120-YL
105-BR
310-PU
308-YL
323-WH
365-YL
168-GN149-PU 616-BU
786-GN
607-PK
120-YL
615-YL115-PK
114-GN 322-GY
320-OR
506-PU
A983-BU
118-GY
118-GY
501-GN
501-GN
501-GN
118-GY
792-OR
500-BR
118-GY
BK-00
BK-00 BK-00
365-YL
323-WH
607-PK
322-GY
616-BU
200-BK
491-PK
A769-GY
B964-YL
200-BK
A768-BU
B965-GY
A768-BU
A769-GY
763-BU
B965-GY
495-GN
A769-GY
A768-BU
B965-GY
142-BU
142-BU
B964-YL
142-BU
491-PK
200-BK
B964-YL
491-PK
200-BK
A771-PU
200-BK
D764-GN
B737-GN
200-BK
D764-GN
A771-PU
200-BK
200-BK
B737-GN
200-BK
124-GN-14
519-PK
103-YL
615-YL
615-YL
122-BU
103-YL
500-BR
501-GN
118-GY
113-OR
129-BU
403-GN
410-WH
B955-YL
B956-PK
B731-WH
B730-OR
A769-GY
A768-BU
185-YL
185-YL
152-BU
A763-GY
B751-YL
B739-WH
B789-BR
B740-OR
B790-OR
578-BU
B786-BU
309-GY
308-YL
310-PU
105-BR
A758-BR
A757-GY
A756-BU
A755-PK
320-OR
306-GN
200-BK-14
103-YL
615-YL
519-PK
124-GN-14
200-BK
103-YL
200-BK
B740-OR
185-YL
B789-BR
B739-WH
B790-OR
B751-YL
578-BU
152-BU
152-BU
575-YL
576-PK
200-BK
200-BK
AM RADIO (NOTE C)
200-BK
200-BK
200-BK-14
BK
YL
235-BK
235-BK
200-BK
616-BU
322-GY
607-PK
323-WH
365-YL
325-PK
325-PK
325-PK
325-PK
325-PK
365-YL
118-GY
501-GN
500-BR
615-YL
200-BK
200-BK
200-BK
B956-PK
B955-YL
410-WH
403-GN
129-BU
113-OR
118-GY
501-GN
500-BR
615-YL
103-YL
122-BU
200-BK
266-BK
266-BK
266-BK
266-BK
200-BK
200-BK
763-BU
763-BU
578-BU
152-BU
575-YL
152-BU
576-PK
B789-BR
B739-WH
B790-OR
B740-OR
200-BK
185-YL
B751-YL
B789-BR
B789-BR
B739-WH
B790-OR
B790-OR
B740-OR
B751-YL
A763-GY
200-BK
185-YL
B790-OR
B790-OR
B789-BR
B790-OR
410-WH
113-OR
200-BK
403-GN
B956-PK
B955-YL
129-BU
129-BU
200-BK
200-BK
320-OR
576-PK
152-BU
575-YL
307-OR
306-GN
307-OR
306-GN
200-BK
575-YL
152-BU
576-PK
320-OR
200-BK
306-GN
307-OR
200-BK
B786-BU
308-YL
310-PU
105-BR
309-GY
A758-BR
A757-GY
A756-BU
A755-PK
307-OR
200-BK
410-WH
113-OR
200-BK
403-GN
201-BK
113-OR
B956-PK
B955-YL
495-GN
576-PK
152-BU
575-YL
200-BK
500-BR
501-GN
200-BK
501-GN
500-BR
200-BK
200-BK
200-BK
615-YL
200-BK
500-BR
501-GN
200-BK
575-YL
152-BU
576-PK
616-BU
200-BK
200-BK
200-BK
200-BK
200-BK
235-BK
200-BK
200-BK
200-BK
322-GY
322-GY
200-BK
322-GY
200-BK
607-PK
200-BK
616-BU
200-BK
200-BK
616-BU
616-BU
200-BK
235-BK
200-BK
322-GY
616-BU
578-BU
152-BU
322-GY
A761-PU
492-GY
405-GY
788-YL
A762-PU
D746-PK
D764-GN
321-BR
332-BU
506-PU
200-BK
200-BK
578-BU
495-GN
616-BU
322-GY
607-PK
323-WH
365-YL
615-YL
112-PU-14
327-PK-10
877-YL-4
101-RD-4
142-BU-14
322-GY
365-YL
323-WH
607-PK
616-BU
101-RD-6
109-OR-6
109-OR-6
124-GN-14
129-BU
185-YL-14
168-GN
105-BR
308-YL
109-OR-10
B737-GN
200-BK
A763-GY
D764-GN
200-BK
A771-PU
B789-BR
615-YL
200-BK
200-BK 200-BK
615-YL
615-YL
200-BK
142-BU-14
122-BU
A763-GY
A770-PK
B730-OR
200-BK
323-WH
B789-BR
118-GY 118-GY
615-YL
122-BU
103-YL
200-BK
511-BR
512-GN
200-BK
200-BK
200-BK
200-BK
200-BK
365-YL
B786-BU
200-BK
575-YL
152-BU
576-PK
105-BR
307-OR
310-PU
310-PU
308-YL
309-GY
A758-BR
A757-GY
A756-BU
A755-PK
200-BK
200-BK
F
E
D
C
B
A
12
9
8 7
118-GY
9 8
7
6 5 4
6 5
4
3
2
1
F
E
D
185-YL
B731-WH
A769-GY
A768-BU
B731-WH
B730-OR
185-YL
2
1
120-YL
122-BU
142-BU-14
142-BU-14
200-BK
A768-BU
3
2
1
C
B
A
200-BK
200-BK
A769-GY
122-BU
120-YL
200-BK
A770-PK
PUMP
BACKUP SW
3T-4405
L7
6
7
8
9
5
3
2
1
10
S 106-0026 E-5
SA S
ATCH
RADIO SW
7X-6386
2
1
FOR MODEL 312 (X171).
FOR MODEL 311 (X169).
NOTE D :
FOR MODEL 312 (X172).
FOR MODEL 311 (X170).
R
R
R
R
T 106-0027 E-5
NOTE C :
ATCH CONVERTER
7T-8000
TO RADIO
ATCH
ANTENNA
106-0036
GROUND
+12 VOLT
+ BATTERY
GROUND
1
2
3
WH/BK-18
WH/RD-18
2
1 RD-18
BK-18
R 7Y-8105 C-7
HEATER UNIT
4I-4650(NOTE C)
4I-1275(NOTE D)
1
2
3
4
5
B
1
2
B
B
B
P
P
N
NB
H
H
G
L3
L11
L2
L1
L3
L1
DA F M
M
M
MF
F
D
E
EE
E
GG
AA
G
G
E
L5
L2
6
7
5
4
3
2
1
FC
EF
AA
HHHH
L2
L1
L22
L11
L2
L1
L8
L10
RELAY PANEL
RELAY PANEL
RELAY PANEL
F
L10
H
A
H
A
A
K K
A K
L4
L5
L4
L5
L9
L9
L6
L6
L8
L6
L5
L4
L12
L12
OPERATOR STATION
B B
B
B
B
B
B
B
B
L22
L22
L21
AA BB CC
FUSE
10A 9W-1442
15A 9W-1441
20A 9W-1446
SAFETY
RELAY
094-2080
CC
FF
L
L
MM
BATTERY
3T-5760
9X-3404(NOTE B)
L
JJ
L20
JJ
KK
L
L
L
L19
L19
L12
L16
L15
L14
L13
KK
LL
MM
FF
GG
LL
KK
KK
LB
B
L
B
B
B
B
A
L
LA
LA
L20
L18
L21
L21
B
B
B
B
EE
EE
B
AA
B
B
B
B
E
R
L
B
P
B
L15
L16
L16
L17L17
L17
L14
L13
L12
L12
DD
B A
AB
B A
AA
AA
A
AAAA
7
ATCH
TRAVEL
ALARM
3T-1444
ATCH
REFRIGERANT SW
(NOTE A)
4I-4573(NOTE C)
5I-3959(NOTE D)
A
CHASSIS
6
7
8
9
5
4
3
2
1
10
WASHER
7T-8890
ATCH
LOWER
WASHER
7T-8890
ENG PICKUP SENSOR -
ENG PICKUP SENSOR +
ENG OIL PRESS. SW
COOLANT SENSOR
GOV ACTR SENSOR
FUEL LEVEL SENSOR
TRAVEL SOLENOID
LEVEL FINISH SOLENOID
TRENCHING SOLENOID
TRAVEL SW
IMPLEMENT SW
MONITOR ALARM
THROTTLE DIAL S4
THROTTLE DIAL S3
THROTTLE DIAL S2
THROTTLE DIAL S1
LOW IDLE SW
RS485 -
RS485 +
BACKUP SW 2
BACKUP SW 1
GOV ACTR -
GOV ACTR +
EPR VALVE -
EPR VALVE +
32
22
12
33
34
21
31
15
OPTION SW 2
OPTION SW 1
OPTION SENSOR
HYD OIL LEVEL SW
ENG OIL LEVEL SW
HYD OIL TEMP SENSOR
COOLANT LEVEL SW
OPTION SOLENOID
ATTACHMENT
ENG SHUTDOWN RELAY
TRAVEL ALARM
BOOM RAISE SW
ALTERNATOR (P TERM.)
KEY SW
BOOM LAMP RELAY
PWM OUT -
PWM OUT +
OPTION RELAY 3
OPTION RELAY 2
OPTION RELAY 1
RS232C RxD
RS232C TxD
HARNESS CODE 4
HARNESS CODE 3
HARNESS CODE 2
HARNESS CODE 1
GND
GND
16
4
3
2
1
BACKUP SW 3
GLOW
+B (24V)
WASHER RELAY
8
9
6
7
20
14
24
WIPER MOTOR RELAY
CHASSIS LAMP RELAY
11
26
17
18
10
16
17
18
19
15
14
13
12
11
20
L18
YL
BU
PU
BK
5
4
3
2
1
SIG
GND
OR
24V+
M
SIG
GND
5V+
ENG GOV
ACTR
4I-5496
STARTER
5I-7716
START
RELAY
ENG
OIL
SW
5I-8005
COOLANT
TEMP
SENDER
5I-7578
ALTERNATOR
096-9299
(NOTE C)
5I-7982
(NOTE D)
ENG
SHUTDOWN
SOL
5I-8008
BLOCK AS.
7Y-5499
DISCONNECT SW
7N-0718 RELAY
PANEL
GG
DD
MAIN
RELAY
3T-0376
ENG
SHUTDOWN
RELAY
9X-8124
HEATER
RELAY
085-5353
6
7
8
9
5
4
3
2
1
10
GROUND
P
S
R
L
10
1
2
3
4
5
9
8
7
6
6
7
8
9
5
4
3
2
1
10
ALT
BREAKER
9S-0174
60A
ATCH
REFUELING
RELAY
7Y-5490
BOOM
LAMP
RELAY
7Y-5490
CAB/CHASSIS
LAMP RELAY
7Y-5490
HORN
RELAY
7Y-5490
WASHER
RELAY
7Y-5490
WIPER
RELAY
7Y-5490
10A
20A
10A
VALVE
5I-8368
TRAVEL
SPEED
4I-5674
TRENCHING
4I-5674
LEVEL
FINISH
4I-5674
HYD OIL
SENDER
4I-5394
AM RADIO (NOTE C)RADIO (NOTE D)
1
2
BOOM
RAISE SW
102-8042
IMPLEMENT SW
102-8041
TRAVEL SW
102-8041
2
1
1
2
PLATFORM
PLATFORM
PLATFORMCHASSIS
109-OR
ATCH A/C
CLUTCH
SOL
7Y-3188
(NOTE C)
7T-8600
(NOTE D)
5
4
3
2
1
5
4
10
1
2
3
4
5
BACKUP
RESISTOR
102-8015
109-OR
ATCH
REFUELING SW
5C-6108
FUEL
SENSOR
7Y-3848
ATCH
REFUELING
PUMP SW AS.
105-9894
-
+
L6
L7
1
2
3
4
5
9
8
7
6
OPERATOR STATION
C
4
3
2
1
10
1
2
3
4
5
9
8
7
6
WIPER
4I-6838
ATCH
LOWER
WIPER
4I-5019
B
PP
PPB
B
C
SPEED
CHANGE SW
7N-8008
GOV
BACKUP SW
3T-4405
ONE TOUCH
LOW IDLE SW
6I-5088
CAB
CIGAR
LIGHTER
9W-0335
ACTION
ALARM
3E-6328
SERVICE
METER
6T-7337
MONITOR
7Y-5500
NEUTRAL
START SW
9W-2150
HORN SW
6I-5088
GROUND
+BATTERY
DATA -
DATA +
2
1
2
OPERATOR STATION
+1S
ATCH
CAB LAMP
5I-8250
1
2
5
+ -
+1
MOTOR
4
3
2
1
OPERATOR STATION
J
3
J
A
J
AA
2
1
CHASSIS
LAMP
5I-8251
ATCH
BOOM
LAMP
5I-8250
ATCH
BOOM
LAMP
5I-8250
HORN
7Y-3920
HORN
7Y-3919
CHASSIS
GY
PU
BR
RED
WHITE
ORANGE
YELLOW
PINK
ABBREV COLOR
BLACK
GRAY
PURPLE
BROWN
DESCRIPTIONSYMBOL
CONNECTOR
ELECTRICAL CONNECTION
TO VEHICLE STRUCTURE
INTERNAL ELECTRICAL
CONNECTION TO SURFACE
OF COMPONENT
BLADE, SPADE, RING,
OR SCREW TERMINAL
BK
PK
YL
OR
WH
RD
GN
BU
GREEN
BLUE
CIRCUIT CONNECTED
CIRCUIT NOT CONNECTED
ATCH WIRE, CABLE,
COMPONENT
L#
CIRCUIT GROUPING
DESIGNATION
IDENT PART NO. LOC
HARNESS AS.
2
5
24
23
4
3
1
37
22
36
40
30
35
38
19
39
29
27
13
25
ENG/PUMP
CONTROLLER
4I-5383
21
23
28
10
1
2
3
4
5
9
8
7
6
MOTOR
ATCH
A/C UNIT
4I-4601(NOTE C)
4I-0470(NOTE D) A
2
MOTOR
1
2
3
4
5
6
5
1
3
4
10
1
2
3
4
5
9
8
6
6
2
1 2
1
1
6
4 4
6
1
3
ENG
PICKUP
5I-7579
AIR
HEATER
5I-7746
CHASSIS
ENG
BB
MOTOR
BAT
MOT
S
G
T
BB
BB
ALT
2
1
5
2
1
USE WITH COLD WEATHER.
NORMALLY OPEN BEFORE REFRIGERANT CHARGE.
NOTE B :
NOTE A :
UNLESS OTHERWISE SPECIFIED ALL WIRE IS 16 GAGE.
COMPONENTS ARE SHOWN INSTALLED ON AFULLY
OPERABLE MACHINE WITH THE KEY AND ENGINE OFF.
THIS SCHEMATIC IS FOR THE 311 AND 312 EXCAVATOR.
GG 7Y-3935 D-9
FF 7Y-3936 D-9
EE 4I-5429 A-9
DD 7Y-3947 D-9
CC 4I-5428 C-9
BB 7Y-3946 C-9
AA 4I-5422 C-9
CABLE AS.
PP 5I-8358 A-5
MM 4I-5451 D-9
LL 4I-5447 D-9
KK 4I-5448 D-9
JJ 7Y-3937 D-7
WIRE AS.
P 7Y-3994 B-2
N 4I-5460 B-2
M 7Y-8245 F-1
L 105-9958 F-9
K 4I-5411 E-5
J 7Y-3868 F-3
H 4I-5463 D-4
G 7Y-3922 D-3
F 5I-8216 C-6
E 111-4712 C-5
D 5I-8217 E-2
C 7Y-8139 C-6
B 105-9920 D-10
A 106-0029 D-10 NOTE F
10
1
2
3
4
5
9
8
7
6
15A
10A
10A10A
10A
15A
2
10A
10A
10A10A
10A
10A
10A
10A
A/C HEATER
CIGAR LIGHTER
BACKUP
REFUELING
KEY SW
LOWER WASHER/WIPER
WASHER/WIPER
TRAVEL ALARM
ENG/PUMP CONT
DOME LAMP
HORN
SOLENOID
MONITOR
RADIO
BOOM LAMP
CAB/CHASSIS LAMP
10A
NEG
POS
NEG
POS
2
1
2
1
2
1
1
2
T
GROUND STRAP
7G-1060
KA
2
1
L3
L5
L9
L4
2
1
2
1
ATCH
SPEAKER
7Y-5505
ATCH
ANTENNA
106-0036
ILLUMI (+)
ACC (+)
BACK UP
GND
SPEAKER (+)
SPEAKER (-)
ANTENNA
ATCH
RADIO
7Y-5433
CAB
ATCH
REFUELING
PUMP
6C-5572
MOTOR
S
-+
ATCH
CAB LAMP
5I-8250
10
1
2
3
4
5
9
8
7
6
2
1
2
1
4
3
2
1
-
+
2
1
ATCH LOWER
WASHER SW
7X-6387
ATCH LOWER
WIPER SW
7X-6388
STARTER KEY
SWITCH
7Y-3918
ENGINE
SPEED
DIAL
7Y-5465
5 S4
S3
S2
S1
COM
4
3
B
C
R2
R1
ACC
START
ON
OFF
BR
PREHT
2
1
3
2
1
2
1
9
8
7
6
DOME
LAMP
096-0721
3
2
1
A T
4
USE WITH MODEL 312 (X171; X172).
USE WITH MODEL 311 (X169; X170).
NOTE F :
NOTE E :
A 106-0028 D-10 NOTE E
CONN 27
CONN 25
CONN 26
CONN 31
CONN 30
CONN 28
CONN 36
CONN 35
CONN 24
CONN 21
CONN 22
CONN 38
CONN 41CONN 34
CONN 17
CONN 60
CONN 59
CONN 59
CONN 19
CONN 18
CONN 14
CONN 13
CONN 48
CONN 12
CONN 57
CONN 43
CONN 49
ALL DASHED LINES ARE ATTACHMENTS.
WIRES THAT HAVE BATTERY VOLTAGE
WHEN THE KEY SWITCH IS OFF.
WIRES THAT HAVE BATTERY VOLTAGE
WHEN THE KEY SWITCH IS ON.
STARTING CIRCUIT.
GAUGE CIRCUIT.
ENG/PUMP CONTROLLER CIRCUIT.
WIPER/WASHER CIRCUIT.
HEATER AND AIR CONDITIONER CIRCUIT.
GROUND CIRCUIT.
ENGINE SHUTDOWN CIRCUIT.
HEATER START AID CIRCUIT.
PROPORTIONAL
REDUCING
CONN 55
CONN 54
CONN 53
CONN 56
CONN 15
CONN 15
CONN 29
CONN 12
CONN 50
CONN 52
CONN 51
CONN 44
CONN 42
CONN 37
CONN 5
CONN 3
CONN 6
CONN 11
CONN 4
CONN 9 CONN 10 CONN 8
CONN 45
CONN 39
CONN 2
CONN 58
(NOTE F)
CONN 1
CONN 23
CONN 20
CONN 33 CONN 32
