John Deere 120D Excavator Diagnistic Operation and Test Manual (TM10736

John Deere 120D Excavator Diagnostic Operation and Test Manual (TM10736 30AUG15)

This official technical manual provides detailed diagnostic, operational, and testing procedures for the John Deere 120D Excavator. It includes troubleshooting for the hydraulic, electrical, and engine systems, along with system performance evaluations, diagnostic trouble codes (DTCs), and test procedures to ensure maximum machine efficiency.

File Format: PDF

Size: 63.86 MB

No. of pages: 903

Language: English

Delivery Method: Instant Download – Access your file immediately after purchase.

📑 Table of Contents Overview:

General Information & Safety

• Recognizing safety information
• Handling chemical products safely
• Preventing unintended machine movement
• Cab guarding for special uses
• Machine inspection and maintenance recommendations

Diagnostic Trouble Codes (DTCs) & Controller Area Network (CAN) Diagnostics

• Main Controller (MCF) diagnostic trouble codes
• ECU (Engine Control Unit) fault codes and troubleshooting
• CAN network resistance and continuity checks
• Abnormal sensor voltage diagnostics

Operational Checkout Procedures

• Engine OFF, Key OFF system checks
• Engine ON, Key ON operational tests
• Blade function, travel mode, and swing speed verification
• Cycle time testing for operational efficiency

Engine System

• Engine speed control system operation
• Fuel injection system troubleshooting
• Cooling system pressure checks and troubleshooting
• Engine power test using turbocharger boost pressure

Electrical System

• Wiring schematics and fuse panel locations
• Battery, alternator, and starter motor diagnostics
• Monitor controller circuit analysis and diagnostics

Power Train

• Track adjustment and undercarriage wear assessment
• Propel motor and travel gear case diagnostics
• Swing motor performance testing

Hydraulic System

• Pilot system pressure regulation
• Hydraulic pump flow testing and calibration
• Control valve function tests and troubleshooting
• Travel motor and swing motor speed calibration

Heating & Air Conditioning System

• Cab air circulation and blower motor troubleshooting
• Air conditioning compressor and refrigerant testing
• Cab heating system and ventilation diagnostics

This John Deere 120D Excavator Diagnostic Operation and Test Manual is an essential resource for technicians, mechanics, and equipment operators, providing comprehensive diagnostics, troubleshooting, and system testing procedures for maintaining peak excavator performance.