John Deere 544G, 544G LL, 544G TC, 624G and 644G Loader Operation and Test Technical Manual (TM1529)

John Deere 544G, 544G LL, 544G TC, 624G and 644G Loader Operation and Test Technical Manual (TM1529 04NOV03)

This official technical manual provides detailed operational theory, diagnostic procedures, testing instructions, and adjustment guidelines for John Deere 544G, 544G LL, 544G TC, 624G, and 644G loaders. Covering systems from engine and transmission to hydraulics, electrical, and air conditioning, this manual is an essential resource for service technicians performing maintenance, troubleshooting, or calibration tasks.

Model Covers:

John Deere 544G, 544G LL, 544G TC Loaders
John Deere 624G Loader
John Deere 644G Loader

File Format: PDF

Size: 9.94 MB

No. of pages: 810

Language: English

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

📑 Included Sections:

Safety and General Information

• Safe handling of fluids, chemical products, and batteries
• ROPS structure integrity, fire prevention, and emergency preparedness
• Proper maintenance tools and work area safety practices

Operational Checkout

• Step-by-step operational tests and diagnostics for all major systems
• Complete machine startup, indicator light behavior, and control response analysis
• Functional checks for brakes, steering, hydraulics, transmission, and electronics

Engine Operation and Testing

• Air intake, fuel system, cooling and lubrication system theory and diagnostics
• Idle adjustment, turbocharger boost testing, fuel system bleeding
• Compression, airflow, and fuel pressure test procedures

Electrical System Diagnostics

• Wiring diagrams, harness locations, and schematic interpretation
• Monitor circuit signal analysis, connector pinouts, and subsystem testing
• Full system coverage: lighting, sensors, starter, charging, safety, HVAC, etc.

Powertrain Operation and Tests

• Torque converter, clutch, axle, differential, and transmission operation theory
• Transmission modulation, pressure testing, and oil cooler evaluation
• Brake diagnostics, accumulator charging, and park brake inspection

Hydraulic System Operation and Tests

• Loader and steering hydraulic circuits, valves, and pump operations
• Drift testing, pressure tests, return-to-dig and boom height adjustments
• Secondary steering and pilot control valve diagnostics

Heating and Air Conditioning

• R12 and R134a refrigerant handling, compressor and expansion valve tests
• Electrical circuit checks and blower system diagnostics
• Charging, evacuating, and leak testing of HVAC system

For complete service information, also see:

544G, 544G LL, 544G TC, 624G, and 644G Repair .......... TM1530
6059 and 6068 Engines .......... CTM8
6076 Engine .......... CTM42
6081 Engine .......... CTM86
Alternators and Starting Motors .......... CTM77
1200 and 1400 Series Axles .......... CTM43

This John Deere Operation and Test Technical Manual is the ultimate reference for maintaining, testing, and diagnosing key systems of the 544G–644G loader series. A must-have for technicians ensuring peak machine performance and uptime.