Caterpillar 330D and 336D Excavator Electrical System
Media Number: UENR2637-02
Publication Date: January 2020
This document provides detailed electrical schematics, component locations, connector information, and symbol definitions for the Caterpillar 330D and 336D Excavators. It is divided into four volumes: Chassis, Cab (Volumes 2 and 3), and Engine.
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|---|---|
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| Find | "CTRL" / "F" |
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Schematic Symbols and Definitions
This section provides definitions and visual representations of various electrical and hydraulic symbols used throughout the schematics. It covers valves, passageways, cylinders, accumulators, pumps, motors, lines, controls, fluid storage, and electrical components.
Wire Group Color Descriptions
The document includes descriptions of wire group colors used in the schematics, categorizing them by function such as Ground Circuit, Engine Control Circuit, and other specific circuits.
Component Location - Volume 1 of 4: Chassis
| Component | Schematic Location | Machine Location |
|---|---|---|
| Alarm - Travel (Attch) | B-12 | 1 |
| Alternator | F-14 | 2 |
| Battery - Front | G-5 | 3 |
| Battery - Front (Attch) | F-5 | 3 |
| Battery - Rear | G-6 | 3 |
| Battery - Rear (Attch) | F-6 | 3 |
| Block - Battery | G-6 | 3 |
| Block - Breaker Box | G-3 | A |
| Breaker - Alternator | G-2 | A |
| Breaker - Heater | G-2 | A |
| Breaker - Main | G-2 | A |
| Camera - Rear View | G-16 | 16 |
| Control - Engine (J1) | G-16 | 6 |
| Control - Machine | F-2 | 5 |
| Control - Product Link | I-14 | 5 |
| Diode - Refueling Power (Attch) | B-4 | H |
| Diode - Start Relay | G-3 | A |
| Ground - FR 1 | F-10 | 27 |
| Ground - FR 2 | E-13 | 28 |
| Ground - FR 3 | E-15 | 6 |
| Ground - FR 4 | A-8 | 13 |
| Ground - FR 5 1 | F-3 | A |
| Ground - FR 5 2 | I-16 | 15 |
| Ground - Product Link Mount | H-14 | 5 |
| Heater - Air | F-15 | 6 |
| Indicator - Air Cleaner | I-10 | 2 |
| Indicator - Hydraulic Oil Filter | A-12 | 8 |
| Motor - AC Condensor Fan | I-10 | 19 |
| Motor - Lower Washer | F-2 | A |
| Motor - Refueling Pump (Attch) | B-4 | H |
| Motor - Starter | F-15 | 6 |
| Motor - Washer | F-2 | A |
| Motor- Priming Pump (Attch) | J-11 | 17 |
| Radio - Product Link | I-16 | 15 |
| Receptacle - Jump Start | G-5 | 4 |
| Relay - Air Heater | F-15 | 7 |
| Relay - Refueling Power | B-4 | H |
| Relay - Refueling Start (Attch) | A-4 | H |
| Relay - Refueling Stop (Attch) | B-4 | H |
| Relay - Start | G-3 | A |
| Resistor - Can Data Link 1 | C-3 | 5 |
| Resistor - Can Data Link 2 | C-3 | 5 |
| Sender - Fuel Level | A-11 | 10 |
| Sender - Hydraulic Oil Temperature | A-12 | 8 |
| Sensor - Ambient Air Temperature | I-11 | 26 |
| Sensor - Engine Speed Pickup | E-15 | 6 |
| Sensor - Fuel Pressure | I-11 | 17 |
| Sensor - Fuel Temperature | J-11 | 17 |
| Sensor - OWLD Pressure (Attch) | C-5 | 25 |
| Sensor - Pump Pressure 1 | B-16 | E |
| Sensor - Pump Pressure 2 | B-16 | E |
| Sensor - Squeeze Pressure (Attch) | C-7 | 21 |
| Sensor - Water Seperator Level (Attch) | I-11 | 17 |
| Solenoid - 1 Way / 2 Way Change (Attch) | C-7 | 22 |
| Solenoid - 1P / 2p Change 1 (Attch) | B-14 | 12 |
| Solenoid - 1P / 2p Change 2 (Attch) | B-14 | 12 |
| Solenoid - AC Compressor Clutch | F-14 | 2 |
| Solenoid - Boom Check 1 (Attch) | C-5 | 25 |
| Solenoid - Boom Check 2 (Attch) | C-5 | 25 |
| Solenoid - Boom Down Line Cutoff (Attch) | D-6 | F |
| Solenoid - Double Action (Attch) | B-14 | 12 |
| Solenoid - Ether Start (Attch) | I-10 | 18 |
| Solenoid - Fine Swing (Attch) | C-5 | 23 |
| Solenoid - Flow Limit (Attch) | A-16 | 11 |
| Solenoid - Heavy Lift (Attch) | F-6 | E |
| Solenoid - Hydraulic Lock | F-6 | F |
| Solenoid - Power Shift Pressure | A-16 | E |
| Solenoid - Quick Coulper (Attch) | B-16 | 24 |
| Solenoid - Quick Coulper High (Attch) | D-6 | 20 |
| Solenoid - Quick Coulper Low (Attch) | D-6 | 20 |
| Solenoid - Radiator Fan Speed | B-16 | E |
| Solenoid - Relief 1 (Attch) | C-7 | 21 |
| Solenoid - Relief 1 Check (Attch) | C-7 | 21 |
| Solenoid - Relief 2 (Attch) | C-7 | 22 |
| Solenoid - Relief 2 Check (Attch) | C-7 | 22 |
| Solenoid - Reversing Fan Change | F-7 | F |
| Solenoid - Single Action 1 (Attch) | B-7 | 21 |
| Solenoid - Single Action 2 (Attch) | B-7 | 22 |
| Solenoid - Stem 1 Extend (Attch) | A-13 | 12 |
| Solenoid - Stem 1 Extend (Attch) | A-14 | 12 |
| Solenoid - Stem 1 Retract (Attch) | A-13 | 12 |
| Solenoid - Stem 1 Retract (Attch) | A-14 | 12 |
| Solenoid - Stem 2 Extend (Attch) | A-13 | 12 |
| Solenoid - Stem 2 Retract (Attch) | A-13 | 12 |
| Solenoid - Stem 3 Extend (Attch) | A-16 | 12 |
| Solenoid - Stem 3 Retract (Attch) | A-16 | 12 |
| Solenoid - Swing Brake | F-6 | F |
| Solenoid - Travel Speed | F-6 | F |
| Solenoid - Travel Straight | F-6 | F |
| Switch - Boom Down Pressure (Attch) | D-6 | F |
| Switch - Boom Raise Pressure (Attch) | E-6 | F |
| Switch - Boom Up / Down Pressure (Attch) | D-6 | F |
| Switch - Coolant Level | I-11 | 17 |
| Switch - Disconnect | F-3 | A |
| Switch - Engine Oil Level | E-15 | 6 |
| Switch - Fuel Pressure | J-11 | 17 |
| Switch - Hammer Return Filter (Attch) | C-11 | 22 |
| Switch - Hydraulic Oil Level | B-12 | 9 |
| Switch - Priming Pump (Attch) | J-11 | 17 |
| Switch - Refueling Level (Attch) | A-11 | 14 |
| Switch - Refueling Start (N.C.) | A-4 | H |
| Switch - Refueling Start (N.O.) | A-4 | H |
Component Location - Volume 2 of 4: Cab
| Component | Schematic Location | Machine Location |
|---|---|---|
| Coil - Exciter (Attch) | D-3 | B |
| Converter - 12 Volt | F-5 | 50 |
| Diode - ACC | E-8 | G |
| Diode - Hydraulic Lock | E-8 | G |
| Ground - FR 7 | I-15 | G |
| Ground - Platform | H-12 | G |
| Heater - Seat (Attch) | E-6 | 51 |
| Indicator - Unit | D-3 | B |
| Joystick - Left Hand (3 Sw) (Attch) | H-4 | C |
| Joystick - Left Hand (Attch) | H-4 | C |
| Joystick - Right Hand (3 Sw) (Attch) | E-4 | B |
| Joystick - Right Hand (Attch) | E-3 | B |
| Key Reader - MSS | D-4 | B |
| Motor - Lower Wiper (Attch) | F-1 | 53 |
| Pedal - Auxilliary LH (Attch) | G-1 | 52 |
| Suspension - Air Seat (Attch) | H-5 | 51 |
| Switch - Auxilliary Pump Pressure Stem 4 | G-1 | 54 |
| Switch - Back Up Gov | C-6 | B |
| Switch - Backup EPR Valve | C-6 | B |
| Switch - Foot (Attch) | G-1 | 52 |
| Switch - High Pressure Stem 1 (Attch) | E-1 | 54 |
| Switch - Horn | H-4 | C |
| Switch - Implement Pressure | E-7 | G |
| Switch - Key | D-3 | B |
| Switch - Medium Pump Pressure Stem 3 | G-1 | 54 |
| Switch - Neutral Start Limit | I-4 | C |
| Switch - One Touch Low Idle | E-5 | B |
| Switch - Secondary Shut Down | C-15 | 55 |
| Switch - Throttle Postion | D-3 | B |
| Switch - Travel L Pressure | F-1 | 53 |
| Switch - Travel R Pressure | F-1 | 53 |
| Switch - Travel Straight Pressure (Attch) | E-1 | 54 |
| Unit - Air Conditioner | F-13 | 56 |
Component Location - Volume 3 of 4: Cab
| Component | Schematic Location | Machine Location |
|---|---|---|
| Alarm - Action | F-1 | 70 |
| Control - Wiper | D-2 | 73 |
| Converter - 12 Volt Power | B-10 | 73 |
| Converter - 12 Volt Radio (Attch) | E-10 | 73 |
| Converter - Radio | B-11 | 73 |
| Diode - Lamp | H-12 | D |
| Diode - Main Relay | B-13 | D |
| Fuses - Switched Power | E-14 | D |
| Fuses - Un-Switched Power | D-11 | D |
| Ground - Cab 1 | D-5 | 73 |
| Ground - Cab 2 | E-9 | 75 |
| Ground - Cab 3 | G-4 | 78 |
| Meter - Service | E-1 | 70 |
| Monitor | G-1 | 79 |
| Motor - Wiper | D-1 | 70 |
| Panel - Switch | E-3 | 71 |
| Relay - Beacon (Attch) | F-12 | D |
| Relay - Boom Float / Disable (Attch) | G-14 | 74 |
| Relay - Boom Lamp | H-12 | D |
| Relay - Cab Lamp | G-12 | D |
| Relay - Chassis Lamp | G-12 | D |
| Relay - Ether (Attch) | E-12 | D |
| Relay - Horn | G-12 | D |
| Relay - LH - Speaker (-) (Attch) | E-16 | 74 |
| Relay - LH - Speaker (+) (Attch) | F-16 | 74 |
| Relay - Main | B-14 | D |
| Relay - Neutral Start | F-12 | D |
| Relay - Priming Pump (Attch) | F-14 | 75 |
| Relay - QC Hydraulic Lock 1 (Attch) | D-16 | 74 |
| Relay - QC Hydraulic Lock 2 (Attch) | C-16 | 74 |
| Relay - QC Hydraulic Lock On (Attch) | D-16 | 74 |
| Relay - QC Hydraulic Lock Priority (Attch) | E-16 | 74 |
| Relay - RH - Speaker (-) (Attch) | F-16 | 74 |
| Relay - RH - Speaker (+) (Attch) | F-16 | 74 |
| Relay - Single (Attch) | F-14 | 74 |
| Relay - Smart Boom Down (Attch) | G-14 | 74 |
| Relay - Smart Boom Up / Down (Attch) | H-14 | 74 |
| Relay - Travel Alarm | F-12 | D |
| Resistor - Backup | H-10 | 57 |
| Resistor - Can Data Link 1 | D-3 | 71 |
| Resistor - Can Data Link 2 | C-8 | 73 |
| Switch - Beacon (Attch) | B-8 | 72 |
| Switch - Fine Swing Control (Attch) | B-4 | 72 |
| Switch - Lower Washer (Attch) | B-6 | 72 |
| Switch - Lower Wiper (Attch) | B-5 | 72 |
| Switch - Over Load Warning (Attch) | B-7 | 72 |
| Switch - Quick Coupler (Attch) | B-3 | 72 |
| Switch - Radio Mute (Attch) | B-5 | 72 |
| Switch - Seat Heater (Attch) | B-7 | 72 |
| Switch - Smart Boom Select (Attch) | B-6 | 72 |
| Switch - Speaker Exchange (Attch) | B-8 | 72 |
| Switch - Under Window Limit (Attch) | E-1 | 77 |
| Switch - Universal Quick Coupler (Attch) | C-2 | 72 |
| Switch - Window Limit | G-1 | 80 |
| Timer - Lamp Delay (Attch) | C-14 | D |
Component Location - Volume 4 of 4: Engine
| Component | Schematic Location | Machine Location |
|---|---|---|
| Control - Engine | E-7 | 90 |
| Relay - Intake Air Heater | C-3 | 91 |
| Sensor - (Cam) Lo Speed / Timing | C-3 | 92 |
| Sensor - (Crank) Hi Speed / Timing | C-3 | 93 |
| Sensor - Atmospheric Pressure | B-3 | 94 |
| Sensor - Coolant Temperature | C-3 | 95 |
| Sensor - Engine Oil Pressure | B-3 | 96 |
| Sensor - Injector Actuation Pressure | B-3 | 97 |
| Sensor - Inlet Air Presssure | B-3 | 98 |
| Sensor - Intake Air Temperature | C-3 | 99 |
| Solenoid - Injector 1 | D-3 | 100 |
| Solenoid - Injector 2 | D-3 | 101 |
| Solenoid - Injector 3 | D-2 | 102 |
| Solenoid - Injector 4 | D-2 | 103 |
| Solenoid - Injector 5 | D-2 | 104 |
| Solenoid - Injector 6 | D-2 | 105 |
| Valve - IAP Control | B-3 | 106 |
Connector Location - Volume 1 of 4: Chassis
| Connector Number | Schematic Location | Machine Location |
|---|---|---|
| CONN 1 | H-16 | 5 |
| CONN 2 | I-15 | 5 |
| CONN 3 | I-15 | 5 |
| CONN 4 | H-15 | 5 |
| CONN 5 | D-15 | 6 |
| CONN 6 | J-14 | A |
| CONN 7 | A-11 | 10 |
| CONN 8 | H-8 | 5 |
| CONN 9 | H-8 | 5 |
| CONN 10 | H-8 | 5 |
| CONN 11 | H-8 | 5 |
| CONN 12 | D-7 | 27 |
| CONN 13 | D-7 | 27 |
| CONN 14 | E-7 | 27 |
| CONN 15 | E-7 | 27 |
| CONN 16 | E-6 | F |
| CONN 17 | B-6 | 23 |
| CONN 18 | B-6 | 25 |
| CONN 19 | B-6 | 25 |
| CONN 20 | A-6 | 13 |
| CONN 21 | A-6 | 13 |
| CONN 22 | A-4 | H |
| CONN 23 | A-4 | H |
| CONN 24 | J-1 | A |
| CONN 25 | H-1 | A |
| CONN 26 | H-1 | A |
| CONN 27 | H-1 | A |
| CONN 28 | H-1 | A |
| CONN 29 | G-1 | A |
| CONN 30 | G-1 | A |
| CONN 31 | G-1 | A |
| CONN 32 | G-1 | A |
Connector Location - Volume 2 of 4: Cab
| Connector Number | Schematic Location | Machine Location |
|---|---|---|
| CONN 24 | G-16 | A |
| CONN 25 | E-16 | A |
| CONN 26 | E-16 | A |
| CONN 27 | E-16 | A |
| CONN 33 | C-14 | 55 |
| CONN 34 | B-14 | 57 |
| CONN 35 | C-13 | 57 |
| CONN 36 | B-12 | 57 |
| CONN 37 | B-11 | 57 |
| CONN 38 | B-10 | 57 |
| CONN 39 | B-9 | 57 |
| CONN 40 | D-11 | 57 |
| CONN 41 | F-10 | A |
| CONN 42A | E-7 | B |
| CONN 42B | E-7 | B |
| CONN 43 | D-7 | B |
| CONN 44 | D-7 | B |
| CONN 45 | D-7 | B |
| CONN 46A | C-7 | B |
| CONN 46A | E-9 | B |
| CONN 46B | C-7 | B |
| CONN 46B | E-8 | B |
| CONN 47 | H-7 | C |
| CONN 48 | H-7 | C |
| CONN 49 | F-5 | 50 |
| CONN 50 | D-5 | B |
| CONN 51 | B-4 | B |
| CONN 52 | C-4 | B |
Connector Location - Volume 3 of 4: Cab
| Connector Number | Schematic Location | Machine Location |
|---|---|---|
| CONN 28 | H-16 | A |
| CONN 29 | H-16 | A |
| CONN 30 | H-16 | A |
| CONN 31 | H-16 | A |
| CONN 32 | I-16 | A |
| CONN 34 | I-11 | 57 |
| CONN 35 | I-10 | 57 |
| CONN 36 | I-9 | 57 |
| CONN 37 | I-8 | 57 |
| CONN 38 | I-7 | 57 |
| CONN 39 | I-6 | 57 |
| CONN 53 | D-13 | D |
| CONN 54 | D-13 | D |
| CONN 55 | B-12 | 73 |
| CONN 56 | E-11 | 73 |
| CONN 57 | B-10 | 73 |
| CONN 58 | D-10 | D |
| CONN 59 | D-10 | D |
| CONN 60 | H-10 | 57 |
| CONN 61 | C-8 | 73 |
| CONN 62 ET | D-8 | 73 |
| CONN 63 | C-4 | 72 |
| CONN 64 | C-4 | 72 |
| CONN 65 | C-4 | 72 |
| CONN 66 | D-4 | 72 |
| CONN 67 | D-4 | 72 |
| CONN 68 | B-4 | 72 |
| CONN 69 | C-3 | 72 |
| CONN 70 | H-3 | 80 |
| CONN 71 | H-3 | 80 |
| CONN 72 | H-3 | 81 |
| CONN 73 | H-3 | 81 |
| CONN 74 | H-2 | 81 |
| CONN 75 | H-2 | 81 |
| CONN 76 | H-2 | 80 |
| CONN 77 | H-2 | 80 |
Connector Location - Volume 4 of 4: Engine
| Connector Number | Schematic Location | Machine Location |
|---|---|---|
| CONN 5 | A-3 | 107 |
| CONN 78 | E-4 | 108 |
| CONN 79 | C-3 | 109 |
Machine Harness Connector and Component Locations
These sections provide visual diagrams illustrating the physical locations of connectors and components on the machine, referencing the schematic locations and machine location codes provided in the tables.
- Visuals for Chassis components and connectors (Pages 16).
- Visuals for Cab components and connectors (Pages 17).
- Visuals for Cab components and connectors (Pages 18).
Specific Component Views
The document also includes specific views of engine components, such as:
- Left Side View - Engine Air Inlet Heater Relay (Page 19)
- Left Side View - Engine (Pages 20)
- Top View - Engine (Page 21)
For detailed wiring information, refer to the wire group color descriptions and the extensive wiring diagrams presented across the volumes.
External Link: Visit SAFETY.CAT.COM for additional safety information.
Copyright © 2020 Caterpillar. All Rights Reserved. CAT, CATERPILLAR, LET'S DO THE WORK, and their respective logos, "Caterpillar Yellow," the "Power Edge" and Cat "Modern Hex" trade dress, as well as corporate and product identity used herein, are trademarks of Caterpillar and may not be used without permission.
