SENR6236May 1994

311 & 312 ExcavatorsElectrical System9LJ262-UP6GK393-UP2KM111-UP

Connector LocationConnector Machine Location

Harness And/OrComponent

Schematic Location Connector

Machine Location

Harness And/OrComponent

Schematic Location

40 Contacts CONN1*A - 1060029Controller

D-12 CONN12 C - 7Y8139 F - 518216

C-6

24 Contacts CONN2*A - 1060029Controller

F-12 CONN30AE - 1114712Monitor

E-2

CONN9D

A - 1060029 B - 1059920

D-11 CONN32 D - 5l8217 Wiper Motor

F-2

CONN8D

A - 1060029 B - 1059920

D-10 CONN12 R - 7Y8105 F - 5l8216

C-7

CONN13A

A - 1060029 F - 5l8216

C-5 CONN43 C - 7Y8139Speaker

B-6

CONN24 A - 1060029 G - 7Y3922

D-3 CONN21BH - 4l5463Lower Wiper Switch

C-3

CONN18B

A - 1060029 H - 4l5463

D-4 CONN29 A - 7Y8105Converter

B-7

CONN17C

A - 1060029 K - 4l5411

E-5 CONN25 A - 1060029 G - 7Y3922

D-3

CONN3D

A - 1060029 L - 1059958

E-9 CONN23 A - 1060029 J - 7Y3868

F-3

CONN5D

A - 1060029 L - 1059958

F-9 CONN39 A - 1060029Refrigerant Low Press Switch

D-12

CONN6D

A - 1060029 L - 1059958

F-9 CONN45 A - 1060029Travel Alarm

D-11

CONN4D

B - 1059920 L - 1059958

E-9 CONN50EB - 1059920Boom Raise Press Switch

B-8

9 Contacts CONN57 C - 7Y8139 Radio

C-6 CONN49 B - 1059920 Fuel Level Sensor

B-6

7 Contacts CONN14AA - 1060029 E - 1114712

C-5 CONN51EB - 1059920Implement Swing Press Switch

C-8

CONN10D

A - 1060029 B - 1059920

D-10 CONN53F8 - 1059920Level Solenoid

A-8

CONN11D

B - 1059920Safety 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 - 1060029Air Conditioner Unit

D-6 CON N56FB - 1059920Proportional Reducing Valve

A-8

CONN19B

A - 1060029 H - 415463

D-4 CONN41 B - 1059920Refueling Pump

A-3

CONN15 A - 1060029 Heater Unit

E-6 CONN34 B - 1059920Refueling Pump Switch

CONN44 B - 1059920Governor Actuator

A-11 CONN42 B - 1059920Speed Sensor

B-10

CONN27B

G - 7Y3922Engine Speed Dial

C-2 CONN52EB - 1059920Travel Press Switch

C-8

CONN58 A - 1060029 A - 1060029

D-12 CONN55FB - 1059920Travel Speed Solenoid

A-8

CONN33 A - 1060029 Lower Wiper Motor

F-2 CONN54FB - 1059920Trenching Solenoid

A-8

Connector Location

Connector Machine LocationHarness And/Or

ComponentSchematic Location Connector

Machine Location

Harness And/OrComponent

Schematic Location

CONN31A

E - 1114712Action Alarm

D-2 CONN20CJ - 7Y3868Horn Switch

F-3

CONN35 F - 5l8216 M - 7Y8245

F-1 CONN26BG - 7Y3922 Low Idle Switch

D-3

CONN22B

H - 4l5463Lower Washer Switch

B3

CONN7 A - 7Y8105Converter

B-7 Plug No.

CONN37 B - 1059920Air Conditioner Clutch Solenoid

C-12 CONN5D Three

CONN36 F-5l8216M - 7Y8245

E-1 CONN6D Two

CONN59C

A - 1060029, S - 1060026 T - 1060027

E-5 CONN3D One

CONN60C

S - 1060026Radio Control Switch

E-4 CONN9D One

CONN8D 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

BulletTerminal

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

910

11

12

1314

15

16

3

4

5

6

8

9

10

11

1214 15

13

16

B

C

D

E1

217

18

19

20

21

22

2324

25

26

27

2829

30

31

32

33 34

7

F

17

18

19 20

21

22

23

24

25

Machine Harness Connector And Component Locations

A1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

3

4

56

8

9

10

11

12

14

1513

16

B

CD

E

1

2

17 18

19

20

21

22

23

24

25

26

27

28

29

30

3132

33347

F

17

18

19 20

21

22

23

24

25

29

9

10

1

2

3 43

4

12

1

2

3

4

5

6

34 5

6 1

2

7

AREA AAREA A

AREA BAREA 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

34

3

4

5

1

2

12

3

3

1

2

AREA E AREA F

Component Location ChartMachine 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

PressureSymbol

TemperatureSymbol

LevelSymbol

FlowSymbol

A AA

2

A AA1

2

325-PK-14C 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

SocketPin

Pin or Socket Number

Wire, Cable, or Harness Assembly Identification

Single Wire Connector

Circuit Number Identification

Wire Gauge

WireColor

Plug Receptacle

9X-1123

Component Part Number

Electrical Schematic Symbols And Definitions

11 12 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 CaterpillarAll Rights Reserved

Printed in U.S.A.

A-3

101112

1011

B731-WHB730-OR105-YL

122-BU

200-BK

122-BU120-YL

122-BU120-YL

RADIO (NOTE D)

12

210-BK

135-BU

200-BK

200-BK

2

200-BK

413

365-YL325-PK

200-BK

323-WH

200-BK

607-PK

616-BU

322-GY200-BK

235-BK200-BK200-BK

607-PK200-BK

323-WH200-BK

365-

YL

325-

PK

200-BK

113-

OR

B75

1-Y

L

513-

OR

306-

GN

A76

3-G

Y

A76

8-B

U

A76

9-G

Y30

9-G

Y40

3-G

N

323-

WH

365-

YL

327-

PK

-10

101-

RD

-410

9-O

R-6

616-

BU

877-

YL-

460

7-P

K14

2-B

U-1

420

0-B

K33

0-Y

LD

746-

PK

309-

GY

403-

GN

D74

6-P

K30

9-G

Y40

3-G

N40

3-G

N30

9-G

YA

769-

GY

A76

8-B

UA

763-

GY

306-

GN

513-

OR

B75

1-Y

L

D76

4-G

NB

965-

GY

B96

4-Y

LB

737-

GN

A77

1-P

U

113-

OR

D74

6-P

KA

762-

PU

A76

1-P

U78

8-Y

L76

3-B

U49

5-G

N49

2-G

Y

BK-00200-BK200-BK267-BK

235-BK235-BK

308-

YL

310-

PU

105-

BR

120-

YL

185-

YL-

1412

9-B

U12

4-G

N-1

432

0-O

R50

0-B

R50

1-G

N10

3-Y

L11

8-G

Y15

2-B

U

615-

YL

113-

OR

A768-BUB731-WHB730-ORB740-ORB739-WHB790-ORB789-BRB955-YLB956-PKB786-BUA755-PKA756-BUA757-GYA758-BR410-WH308-YL578-BU519-PK513-OR

513-

OR

519-

PK

578-

BU

308-

YL

410-

WH

A75

8-B

RA

757-

GY

A75

6-B

UA

755-

PK

B78

6-B

UB

956-

PK

B95

5-Y

LB

789-

BR

B79

0-O

RB

739-

WH

B74

0-O

RB

730-

OR

B73

1-W

H

A76

8-B

U

235-BK235-BK

267-BK200-BK200-BK

D764-GND746-PKA762-PU788-YL405-GY492-GYA761-PU495-GN763-BUB964-YLB965-GYB737-GNA771-PU491-PK

506-PU332-BU786-GN121-YL791-PK792-ORA983-BU184-BU877-YL

519-PK513-OR321-BR

121-YL

121-

YL

321-

BR

513-

OR

519-

PK

321-BR121-YL

519-PK513-OR

235-BK

267-BK786-GN

308-YL410-WHA758-BRA757-GYA756-BUA755-PKB786-BUB956-PKB955-YLB789-BRB790-ORB739-WHB740-ORB730-ORB731-WHA768-BU877-YL184-BUA983-BU792-OR791-PK

491-PKA771-PUB737-GNB965-GYB964-YL763-BU495-GN

491-

PK

405-

GY

124-GN-14519-PK615-YL103-YL200-BK-14

200-BK

578-BU200-BK200-BK506-PU

332-BU321-BRD764-GND746-PKA762-PU788-YL405-GY492-GYA761-PU495-GN

791-PK792-ORA983-BU184-BU877-YLA768-BUB731-WHB730-ORB740-ORB739-WHB790-ORB789-BRB955-YL

267-BK267-BK266-BK265-BK264-BK235-BK

763-BU

B956-PK

B964-YL

B786-BU

B965-GYB737-GNA771-PU491-PK

A755-PKA756-BUA757-GYA758-BR410-WH308-YL

786-GN

235-BK

RD

-00

RD-00

235-BK

513-

OR

D74

6-P

K10

9-O

R-6

403-

GN

309-

GY

200-

BK

-6

492-

GY

405-

GY

306-

GN

330-

YL

101-

RD

-4

101-RD-4330-YL306-GN405-GY492-GY200-BK-6309-GY403-GN109-OR-6D746-PK513-OR

877-

YL-

4A

762-

PU

788-

YL

327-

PK

-10

200-

BK

200-

BK

200-

BK

200-

BK

-6

113-

OR

200-

BK

A76

1-P

UA

763-

GY

B75

1-Y

L

RD-00

RD

-00

101-RD-4

330-YL306-GN

405-GY

492-GY

200-

BK

200-

BK

200-BK-6309-GY

403-GN109-OR-6D746-PK

200-

BK

200-BK513-OR

B751-YLA763-GYA761-PU200-BK113-OR

200-BK-6200-BK200-BK200-BK200-BK-10

200-BK-10327-PK-10

327-PK-10788-YLA762-PU877-YL-4

877-YL-4

B73

7-G

N

D76

4-G

N

200-

BK

A77

1-P

U

491-

PK

B96

4-Y

L

B96

5-G

Y76

3-B

UA

768-

BU

A76

9-G

Y

101-RD-14

112-PU-14

112-PU-14112-PU-14

310-PU308-YL320-OR

152-BU103-YL

152-BU118-GY121-YL184-BU103-YL114-GN

120-YL113-OR500-BR118-GY501-GN615-YL

BK

-00

149-

PU

120-

YL

113-

OR

115-

PK

142-

BU

-14

615-YL501-GN118-GY500-BR113-OR

184-BU

786-GN

332-BU

506-PU

121-YL

792-OR

791-PK

A983-BU

877-YL

616-BU607-PK

323-WH365-YL322-GY

101-RD-14

112-PU-14112-PU-14112-PU-14112-PU-14112-PU-14

332-BU

200-

BK

200-BK

BK

-00

BK-00101-RD-4

310-PU

877-YL

877-YL-4

327-PK-10

109-OR-10

109-OR-6200-BK

112-PU-14112-PU-14112-PU-14112-PU-14

BKRD

877-YLA983-BU

791-PK792-OR

121-YL

506-PU332-BU786-GN184-BU

113-OR

615-YL

152-BU118-GY103-YL501-GN500-BR

320-OR124-GN-14129-BU185-YL-14

D746-PKD746-PK200-BK330-YL309-GY309-GY403-GN403-GN

WH/YLBK

WH/BU

YL

WH/GN

101-RD-6101-RD-14101-RD-14

120-YL

105-BR310-PU308-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-BU118-GY

118-GY

501-GN

501-GN501-GN118-GY

792-OR

500-BR

118-GY

BK

-00

BK-00 BK-00

365-YL323-WH607-PK322-GY616-BU

200-BK491-PK

A769-GY

B964-YL

200-BK

A768-BU

B965-GY

A768-BUA769-GY

763-BUB965-GY

495-GN

A769-GYA768-BU

B965-GY

142-BU

142-BU

B964-YL

142-BU

491-PK

200-BK

B964-YL491-PK200-BK

A771-PU200-BKD764-GN

B737-GN

200-BKD764-GN

A771-PU

200-BK

200-BK

B737-GN

200-BK

124-GN-14519-PK103-YL615-YL615-YL

122-BU

103-YL500-BR501-GN118-GY113-OR129-BU403-GN410-WHB955-YLB956-PK

B731-WHB730-ORA769-GYA768-BU185-YL185-YL152-BUA763-GYB751-YLB739-WHB789-BRB740-ORB790-OR578-BUB786-BU309-GY308-YL310-PU105-BRA758-BRA757-GYA756-BUA755-PK320-OR306-GN

200-BK-14103-YL615-YL519-PK124-GN-14

200-BK103-YL 20

0-B

KB

740-

OR

185-

YL

B78

9-B

RB

739-

WH

B79

0-O

R

B75

1-Y

L

578-

BU

152-

BU

152-

BU

575-

YL

576-

PK 20

0-B

K20

0-B

K

AM RADIO (NOTE C)

200-

BK

200-

BK

200-

BK

-14

BKYL

235-BK

235-BK200-BK616-BU322-GY607-PK323-WH365-YL325-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

B95

6-P

KB

955-

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

B78

9-B

RB

739-

WH

B79

0-O

RB

740-

OR

200-

BK

185-

YL

B75

1-Y

L

B789-BRB789-BRB739-WHB790-ORB790-ORB740-OR

B751-YL

A763-GY

200-BK

185-YL

B790-ORB790-OR

B789-BRB790-OR

410-

WH

113-

OR

200-

BK

403-

GN

B95

6-P

KB

955-

YL

129-

BU

129-BU200-BK

200-BK320-OR

576-PK152-BU575-YL

307-OR

306-GN

307-OR306-GN

200-BK575-YL152-BU576-PK

320-OR

200-BK

306-GN

307-OR

200-

BK

B78

6-B

U

308-

YL

310-

PU

105-

BR

309-

GY

A75

8-B

RA

757-

GY

A75

6-B

UA

755-

PK

307-

OR

200-

BK

410-WH113-OR

200-BK

403-GN

201-BK113-ORB956-PKB955-YL

495-GN

576-PK152-BU575-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-BU200-BK

200-BK

200-

BK

200-

BK

200-

BK

235-

BK

200-

BK

200-BK200-BK322-GY322-GY

200-BK322-GY

200-BK607-PK

200-BK616-BU

200-BK200-BK616-BU616-BU

200-BK235-BK

200-BK322-GY

616-BU

578-BU152-BU

322-

GY

A761-PU492-GY405-GY788-YLA762-PUD746-PKD764-GN

321-BR332-BU

506-PU

200-BK200-BK578-BU

495-

GN

616-

BU

322-

GY

607-

PK

323-

WH

365-

YL

615-YL

112-PU-14

327-PK-10877-YL-4101-RD-4

142-BU-14322-GY365-YL323-WH607-PK616-BU

101-RD-6109-OR-6

109-OR-6

124-GN-14129-BU185-YL-14168-GN105-BR

308-YL

109-OR-10

B737-GN

200-BK

A76

3-G

Y

D764-GN200-BK

A771-PU

B789-BR

615-YL200-BK

200-BK 200-BK615-YL

615-YL200-BK

142-BU-14

122-BU

A76

3-G

Y

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-YL152-BU576-PK

105-BR307-OR

310-

PU

310-PU

308-YL

309-GY

A758-BRA757-GYA756-BUA755-PK200-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-WHB730-OR185-YL

21

120-YL122-BU

142-

BU

-14

142-BU-14

200-

BK

A768-BU

3 2 1

C

B

A

200-

BK

200-

BK

A769-GY

122-BU120-YL

200-

BK

A770-PK

PUMPBACKUP SW3T-4405

L7

67

89

5

3

21

10

S 106-0026 E-5

SA S

ATCHRADIO SW7X-6386

21

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 CONVERTER7T-8000

TO RADIO

ATCHANTENNA106-0036

GROUND+12 VOLT

+ BATTERYGROUND

1 2

3

WH/BK-18WH/RD-18

2 1 RD-18

BK-18

R 7Y-8105 C-7

HEATER UNIT4I-4650(NOTE C)4I-1275(NOTE D)

1

2

34

5

B

1 2

B

B

B

P

PN

NB

H

H

G

L3

L11

L2

L1

L3

L1

DA F MM

MMF

F

D

E

EE

E

GG

AA

G

G

E

L5

L2

6 75 43 21

FC

EF

AA

HHHH

L2

L1

L22

L11

L2

L1

L8

L10

RE

LAY

PA

NE

L

RELAY PANEL

RELAY PANEL

F

L10

H

A

H

A

A

K KA 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

L22L21

AA BB CC

FUSE10A 9W-144215A 9W-144120A 9W-1446

SAFETYRELAY094-2080

CC

FF

L

L

MM

BATTERY3T-57609X-3404(NOTE B)

L

JJ

L20

JJ

KKL L

L

L19

L19

L12

L16

L15

L14

L13

KK

LL

MMFFGGLLKK

KK

LB

B

L

B

B

B

B

A L

LA

LAL20

L18

L21

L21

B

B

B

B

EE

EE

B

AAB

B

B

B

E R

LBP

B

L15

L16

L16

L17L17

L17

L14

L13

L12

L12

DD

BAA

BBA

AA

AA

A

AAAA

7

ATCHTRAVELALARM3T-1444

ATCHREFRIGERANT SW(NOTE A)4I-4573(NOTE C)5I-3959(NOTE D)

A

CHASSIS

67 8 954 321

10

WASHER7T-8890

ATCHLOWERWASHER7T-8890

ENG PICKUP SENSOR -ENG PICKUP SENSOR +

ENG OIL PRESS. SWCOOLANT SENSOR

GOV ACTR SENSORFUEL LEVEL SENSOR

TRAVEL SOLENOIDLEVEL FINISH SOLENOID

TRENCHING SOLENOIDTRAVEL SW

IMPLEMENT SW

MONITOR ALARMTHROTTLE DIAL S4THROTTLE DIAL S3THROTTLE DIAL S2THROTTLE DIAL S1

LOW IDLE SWRS485 -RS485 +

BACKUP SW 2BACKUP SW 1

GOV ACTR -GOV ACTR +

EPR VALVE -EPR VALVE +

322212

3334213115

OPTION SW 2OPTION SW 1

OPTION SENSORHYD OIL LEVEL SWENG OIL LEVEL SW

HYD OIL TEMP SENSOR

COOLANT LEVEL SWOPTION SOLENOID

ATTACHMENTENG SHUTDOWN RELAY

TRAVEL ALARMBOOM RAISE SW

ALTERNATOR (P TERM.)

KEY SW

BOOM LAMP RELAY

PWM OUT -PWM OUT +

OPTION RELAY 3OPTION RELAY 2OPTION RELAY 1

RS232C RxDRS232C TxD

HARNESS CODE 4HARNESS CODE 3HARNESS CODE 2HARNESS CODE 1

GNDGND

16

4321

BACKUP SW 3GLOW

+B (24V)WASHER RELAY

8967

20

1424

WIPER MOTOR RELAYCHASSIS LAMP RELAY

11

26171810

16

17

18

19

151413

12

11

20

L18

YL

BU

PUBK

54321

SIGGND

OR24V+

M

SIGGND5V+

ENG GOVACTR4I-5496

STARTER5I-7716

STARTRELAY

ENGOILSW5I-8005

COOLANTTEMPSENDER5I-7578

ALTERNATOR096-9299(NOTE C)

5I-7982(NOTE D)

ENGSHUTDOWNSOL5I-8008

BLOCK AS.7Y-5499

DISCONNECT SW7N-0718 RELAY

PANEL

GGDD

MAINRELAY3T-0376

ENGSHUTDOWNRELAY9X-8124

HEATERRELAY085-5353

6

7

89

54

3

2

1

10

GROUNDP

SR

L

10

12345

9876

6789

54321

10

ALTBREAKER9S-0174

60A

ATCHREFUELINGRELAY7Y-5490

BOOMLAMPRELAY7Y-5490

CAB/CHASSISLAMP RELAY7Y-5490

HORNRELAY7Y-5490

WASHERRELAY7Y-5490

WIPERRELAY7Y-5490

10A20A10A

VALVE5I-8368

TRAVELSPEED4I-5674

TRENCHING4I-5674

LEVELFINISH4I-5674

HYD OILSENDER4I-5394

AM RADIO (NOTE C)RADIO (NOTE D)

12

BOOMRAISE SW102-8042

IMPLEMENT SW102-8041

TRAVEL SW102-8041

21

12

PLATFORM

PLATFORM

PLATFORMCHASSIS

109-OR

ATCH A/CCLUTCHSOL7Y-3188(NOTE C)7T-8600(NOTE D)

5

43

2

1

5 4

10

1 2 34 5

BACKUPRESISTOR102-8015

109-OR

ATCHREFUELING SW5C-6108

FUELSENSOR7Y-3848

ATCHREFUELINGPUMP SW AS.105-9894

-+

L6

L7

12 3 4 59876

OPERATOR STATION

C

4

3

2

1

10 1 23 4 59 876

WIPER4I-6838

ATCHLOWERWIPER4I-5019

B

PP

PPB

B

C

SPEEDCHANGE SW7N-8008

GOVBACKUP SW3T-4405

ONE TOUCHLOW IDLE SW6I-5088

CAB

CIGARLIGHTER9W-0335

ACTIONALARM3E-6328

SERVICEMETER6T-7337

MONITOR7Y-5500

NEUTRALSTART SW9W-2150

HORN SW6I-5088

GROUND+BATTERYDATA -DATA +

2 1

2

OPERATOR STATION

+1S

ATCHCAB LAMP5I-8250

12

5

+ -

+1MOTOR

43 21

OPERATOR STATION

J

3

J

A

J

AA

21

CHASSISLAMP5I-8251

ATCHBOOMLAMP5I-8250

ATCHBOOMLAMP5I-8250

HORN7Y-3920

HORN7Y-3919

CHASSIS

GYPUBR

REDWHITEORANGEYELLOWPINK

ABBREV COLOR

BLACKGRAYPURPLEBROWN

DESCRIPTIONSYMBOL

CONNECTOR

ELECTRICAL CONNECTIONTO VEHICLE STRUCTURE

INTERNAL ELECTRICALCONNECTION TO SURFACEOF COMPONENT

BLADE, SPADE, RING,OR SCREW TERMINAL

BKPKYLORWHRD

GNBU

GREENBLUE

CIRCUIT CONNECTED

CIRCUIT NOT CONNECTED

ATCH WIRE, CABLE,COMPONENT

L# CIRCUIT GROUPINGDESIGNATION

IDENT PART NO. LOC

HARNESS AS.

25

2423

43

1

37

22

364030

35

38

19

39292713

25

ENG/PUMPCONTROLLER4I-5383

21

2328

10

1

2

3

45

9

87

6

MOTOR

ATCHA/C UNIT4I-4601(NOTE C)4I-0470(NOTE D) A

2

MOTOR

12 3 45 6

5

134

10 1 23 4 59 8

6

6

21 2

1

16

4 4

613

ENGPICKUP5I-7579

AIRHEATER5I-7746

CHASSIS

ENG

BB

MOTOR

BATMOT

SG

T

BB

BB

ALT

21

5

21

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 AFULLYOPERABLE MACHINE WITH THE KEY AND ENGINE OFF.

THIS SCHEMATIC IS FOR THE 311 AND 312 EXCAVATOR.

GG 7Y-3935 D-9FF 7Y-3936 D-9EE 4I-5429 A-9DD 7Y-3947 D-9CC 4I-5428 C-9BB 7Y-3946 C-9AA 4I-5422 C-9

CABLE AS.

PP 5I-8358 A-5MM 4I-5451 D-9LL 4I-5447 D-9KK 4I-5448 D-9JJ 7Y-3937 D-7

WIRE AS.

P 7Y-3994 B-2N 4I-5460 B-2M 7Y-8245 F-1L 105-9958 F-9K 4I-5411 E-5J 7Y-3868 F-3H 4I-5463 D-4G 7Y-3922 D-3F 5I-8216 C-6E 111-4712 C-5D 5I-8217 E-2C 7Y-8139 C-6B 105-9920 D-10A 106-0029 D-10 NOTE F

10

12345

9876

15A10A10A10A

10A15A

2

10A10A10A10A

10A10A10A10A

A/C HEATERCIGAR LIGHTERBACKUPREFUELINGKEY SW

LOWER WASHER/WIPERWASHER/WIPERTRAVEL ALARMENG/PUMP CONTDOME LAMPHORN

SOLENOIDMONITORRADIOBOOM LAMPCAB/CHASSIS LAMP10A

NEGPOSNEGPOS

21

21

21

12

T

GROUND STRAP7G-1060

KA

21

L3

L5

L9

L4

21

21

ATCHSPEAKER7Y-5505

ATCHANTENNA106-0036

ILLU

MI (

+)

AC

C (

+)

BA

CK

UP

GN

DS

PE

AK

ER

(+

)S

PE

AK

ER

(-)

AN

TE

NN

A

ATCHRADIO7Y-5433

CAB

ATCHREFUELINGPUMP6C-5572

MOTORS

-+

ATCHCAB LAMP5I-8250

10 123 4 5987 6 21

21

43

21

-+

21

ATCH LOWERWASHER SW7X-6387

ATCH LOWERWIPER SW7X-6388

STARTER KEYSWITCH7Y-3918

ENGINESPEEDDIAL7Y-5465

5 S4S3S2S1COM

43

B

C

R2

R1

ACCSTART

ONOFF

BR PREHT

21

321

21

9876

DOMELAMP096-0721

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 60CONN 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 VOLTAGEWHEN 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.PROPORTIONALREDUCING

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 45CONN 39

CONN 2

CONN 58(NOTE F)

CONN 1

CONN 23

CONN 20

CONN 33 CONN 32