Wire Number
Wire Description
Wire Color
Description
Wire Number
Wire Color
Power Circuits
Description
RD
Bat (+)
500
BR
Wiper - Front (Park)
102
BU
Hd Lmp
501
GN
Wiper - Front (Low)
105
BR
Key Sw
502
OR
Wiper - Front (HI)
112
PU
Main Power Relay Output
503
BR
Wiper - Rear (Park)
113
OR
Opr Mon Panel B (+) Switched
504
YL
Wiper - Rear (Low)
116
BR
Aux Ckt
505
BU
Wiper - Rear (HI)
118
GY
Aux Ckt
506
PU
Washer - Front
119
PK
Aux Ckt
513
OR
A/C Compressor/Refrigerant Pressure SW
121
YL
Backup Alarm Lamp
515
GY
Blower Motor (HI)
123
WH
Aux Ckt
516
GN
Blower Motor (Medium)
124
GN
A/C
517
BU
Blower Motor (Low)
128
PK
Aux Ckt
520
WH
Opr A/C SW To Thermostat/Fuse
143
BR
Aux Ckt
521
YL
A/C SW To Refrigerant SW
157
YL
Aux Ckt
522
WH
A/C Clutch To Thermostat SW
161
PK
Aux Ckt
536
WH
Hazard SW To Turn SW
194
GN
Aux Ckt
537
GN
Turn Signal SW To Flasher
538
BR
Hazard Indicator
552
WH
Four Wheel Drive Sol
Ground Circuits
Connectors
Machine Location
B-9
5 Contacts
*
E - 9R9541 H - 9R9544
12 Contacts
E - 9R9541
3
L - 9R9543 E - 9R9541
3
E - 9R9541 D - 9R9549
7
E - 9R9541 B - 9R9550
6
6 Contacts
GG - 9R9535 D - 9R9549
9
E-3
*
GG-9R9535
A-2, F-3
Head/Position Turn Lamp A - 9R9558
D-3
Front Wiper Motor A - 9R9558
E-9
Rear Wiper Motor (Upper) B - 9R9550
11
A-9
NN - 9R9567
A-8
12
B-4
13
E-2
14
B - 9R9550
A-9
C - 9R9537 TT - 9R9098
F-7
UU - 9R9443 B - 9R9550
F-9
NN - 9R9567
C-4
E - 9R9541 E - 9R9541
8
*
A-6
G - 9R9542
* = Connector is located at the component.
Main Chassis Basic Machine Circuits
564
GY
Rear Wiper Interrupt SW To Wiper SW
304
WH
Starter Relay No. 1 Output
568
GN
Waring Buzzer To Diodes
306
GN
Starter Relay Coil To Neut Start SW Or Key SW
576
PK
Wiper - Aux (Lo)
307
OR
Key Sw To Nuet Start SW
577
PU
Wiper - Aux (Hi)
308
YL
Main Power Relay Coil
A512
GN
Rear Interrupt SW To Wiper Motor
309
GY
Alternator Regulator Term.
310
PU
Start Aid SW To Start Aid Sol
603
PK
Rotary Beacon
311
WH
Start Aid Sol To Temp SW
604
OR
Stop Turn lamp
321
BR
Bckp Alarm
605
YL
Turn Lamp - Left
Lighting Circuits
Warning Horn (Forward)
606
Monitoring Circuits
607
GY PK
SENR5818 December 1992
Schematic Location
Harness and/Or Components
4 Contacts
B - 9R9550
8 Contacts
B-7
B-7
H - 9R9544
5
BK
GY
Schematic Location
K - 9R9557
2
200
322
Harness and/Or Components A - 9R9558
1
Accessory Circuits
101
HARNESS CONNECTOR LOCATION CHART
Machine Location
Connectors
Part No.
Turn Lamp - Right
8N1693
Flood Lamp - Front
405
GY
Opr Mon Oil Press. (Low Setting)
608
GN
Flood Lamp - Rear
406
PU
Opr Mon Coolant Temp
610
OR
Head Lamp Basic
419
YL
Opr Mon Parking Brake
611
PU
Head Lamp Hi
441
OR
Eng Coolant Temp Gauge
614
PU
Park/Tail/Dash Lamp
443
YL
Power Train Temp Gauge
617
BR
Tail/Position Lamp - Left (Road Pkg)/Width
447
PK
Fuel Level Gauge
618
YL
Tail/Position Lamp - Right (Road Pkg)/Width
450
YL
Tach Sender
619
GN
Head Lamp Lo
634
WH
Head lamp SW To Work/Head Lamp Jumper
762
YL
Bucket Positioner Sol SW
766
GN
XMSN Disconnect Sol
Off Machine Switch Specification
Function
Actuate
Deactuate
Contact Position
37.8 ± 2.8°C
26.7°C MIN
Normally
(100 ± 5°F)
(80°F MIN)
Closed
107.2 ± 2.8°C
93°C MIN
Normally
(225 ± 5°F)
(196°F MIN)
Closed
Coolant Temperature (Start Aid)
6T2665
Coolant Temperature
416, 426, 428, 436, And 438 Series II Backhoe Loaders With European Cab Electrical System 416: 5PC15429-UP
428: 6TC10381-UP
426: 7BC5259-UP
436: 5KF1553-UP
438: 3DJ2161-UP
Control Circuits
Resistor, Sender and Solenoid Specifications
Component Description
Part No.
Resistance (Ohms)¹
Resistor - Alternator
8C4110
22 ± 1.1
Resistor - Blower Motor Speed
7T3828
Overall 1.0 ± .1; Tap0.5 ± .05
Solenoid - A/C Clutch
8T8812
3.5 ± 0.15
Solenoid - Bucket Positioner
9T7304
18.0
Solenoid - Start Aid
3T9493
1.5
¹ At room temperature unless otherwise noted.
Printed in U.S.A.
© 1992 Caterpillar All Rights Reserved
Harness And Wire Electrical Schematic Symbols Component Location
Machine Location
Component
Schematic Location
Machine Location
Component
Schematic Location
1
Alarm - Backup
B-9
15
Solenoid - Front Drive
C-2
A
Alarm - Fault
C-3
16
Solenoid - Start Aid
F-2
2
Alternator
C-1
17
Solenoid - Transmission Neutralizer
C-2
3
Batteries
F-S
18
Switch - Backup Alarm
C-2
C
Breaker - Running Lamp
C-8
B
Switch - Beacon
D-7
C-9
A
Switch - Blower (Heater And Air Cond)
E-3
C-B, C-3
19
Switch - Bucket Positioner
A-1
20
Switch - Coolant Temperature
C-2
A
Flasher
C
Fuse - Holders
B
Gauge - Converter Temperature
D-8
B
Gauge - Coolant Temperature
D-8
B
Gauge - Fuel
D-9
21
Switch - Coolant Temperature (Start Aid)
Gauge - Tachometer
D-9
A
Switch - Dimmer
E-4
4
Horn - Forward
D-1
22
Switch - Engine Oil Pressure
D-1
B
Meter - Service
D-9
A
Switch - Forward Horn
C-4
Meter - Volt
D-8
B
Switch - Front Drive
Motor - Blower
D-3
B
Switch - Front Wiper
C-6
A
Motor - Fan
E-7
B
Switch - Hazard
D-7
A
Motor - Front Wiper
D-3
B
Switch - Head Lamp/Front Flood
D-7
A
Motor - Rear Wiper (Lower)
F-8
B
Switch - Key Start
D-8
A
Motor - Rear Wiper (Upper)
E-9
A
Switch - Lamp Test
C-4
S
Motor - Starter
E-2
23
Switch - Neutral/Start
C-2
6
Motor - Windshield Washer
F-4
24
Switch - Parking Brake
F-6
C
Relay
C-8
B
Switch - Rear Dual Wiper
D-6
C
Relay - Main
C-7
B
Switch - Rear Flood Lamp
D-7
C
Relay - Start
C-7
26
Switch - Refrigerant
F-1
7
Resistor - Alternator Field
D-7
B
Switch - Running Lamp
D-6
A
Resistor - Blower Motor Speed
D-3
B
Switch - Start Aid
D-7
8
Sender - Converter
C-2
A
Switch - Thermostat
C-3
9
Sender - Coolant Temperature
C-1
A
Switch - Turn Signal
E-4
10
Sender - Fuel
A-6
27
Switches - Brake (Stop Light)
D-4
12
Solenoid - Air Conditioner Clutch
D-1
13
Solenoid - Bucket Positioner
A-4
14
Solenoid - Engine Shutdown
D-2
A = Components in operator compartment.
A A
Switches - Transmission Neutralizer Switches - Wiper Disconnect
D-6, D-4 E-8
Typical representation of a Deutsch connector. The plug contains all sockets and the receptacle contains all pins.
2 T
Pressure Symbol
3
14
12
1
B 1
C
2
5
16
5
14
22
4
12
15
8
18 27 17
11
2
23
20
C
Normally open switch that will close with an increase of a specific condition (temp-press-etc.).
A
A 325-PK-14
9 21
19
7
Pin or Socket Number
Flow Symbol
26
Pin
Normally open switch that is closed due to an applied condition, and will open again with a specific decrease in that condition.
13 10
AA 1
Normally closed switch that will open with an increase of a specific condition.
19
C 1
2
1
14 11
7
3
24
12 7
18
9 8
13
12
6
16
17 27 8
10 3
5
23 15
14
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.
21 20
22
Wire Gauge
FUSE - A component in an electrical circuit that will open the circuit if too much current flows through it.
4
5
200-BK-14
Electrical Schematic Symbols And Definitions
The circle indicates that the component has screw terminals and a wire can be disconnected from it.
13
325-PK-14
Circuit Number Identification
Normally closed switch that is open due to an applied condition, and will close again with a specific decrease in that condition. A
9X-1123
Wire Color
Socket
2
B
Component Part Number
Single Wire Connector
6
A
8
Typical representation of a Sure-Seal connector. The plugand receptacle contain both pins and sockets.
Wire, Cable, or Harness Assembly Identification
13
9
7
Level Symbol
6
3
24
Temperature Symbol
1 2
1 2
Receptacle
Plug
C-6
A
AA 1
Electrical Schematic Symbols And Definitions
C-1
B
B
A
No circle indicates that the wire cannot be disconnected from the component.
9 7 26
T
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.
6
This indicates that the component has a wire connected to it that is connected to ground.
B = Components in operator compartment - Right console. C = Components on relay panel (inside right console).
Machine Harness Connector and Component Locations
This indicates that the component does not have a wire connected to ground. It is grounded by being fastened to the machine.
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. 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.