General Troubleshooting Information
Visual inspections are the first steps in order to troubleshoot a problem. When the visual inspections are complete and the problem is not fully understood, perform operational checks. After visual inspections and operational checks are complete and the problem is not fully understood, perform test procedures. These procedures will help identify system problems. These procedures are located in the Testing and Adjusting module for your machine.
For the locations of your individual system components, refer to the Systems Operation module for your machine.
For more information on the electrical system, refer to the Electrical Schematic for your machine.
For more information on the brake and hydraulic fan system, refer to the Brake and Hydraulic Fan Schematic for your machine.
Caterpillar Information System:
621H, 623H and 627H Wheel Tractor-Scrapers Braking and Hydraulic Fan System Visual Inspection
621H, 623H and 627H Wheel Tractor-Scrapers Engine Supplement Water Temperature Regulator - Remove and Install - Tractor
621H, 623H and 627H Wheel Tractor-Scrapers Engine Supplement Belt Tensioner - Remove and Install - Tractor
621H, 623H and 627H Wheel Tractor-Scrapers Braking and Hydraulic Fan System Machine Preparation for Troubleshooting
980K Wheel Loader Power Train Transmission Hydraulic Control Operation
992K Wheel Loader Axle Breaker Relief Valve - Clean
980K Wheel Loader Machine Electronic Control System General Information
D6K2 Track-Type Tractor Mounting and Dismounting
980K Wheel Loader Electronic Control Module (ECM) - Configure
D6K2 Track-Type Tractor Declaration of Conformity
D3K2, D4K2 and D5K2 Track-Type Tractor Systems Charge Relief Valve - Test and Adjust
CG137-08 and CG137-12 Engines Ignition System Timing - Check/Adjust
854K Wheel Dozer and 992K Wheel Loader Machine Systems Electrohydraulic Control (Joystick) - Remove and Install
621H, 623H and 627H Wheel Tractor-Scrapers Engine Supplement Turbocharger - Remove and Install - Tractor
D11T Track-Type Tractor Engine Supplement Prelubrication Oil Pump - Remove and Install
320E and 323E Excavators Machine System Specifications Auxiliary Hydraulic Lines
D5R and D6N Track-Type Tractor Power Train Transmission Hydraulic Control Valve - Disassemble
C3.4B Industrial Engine Fan Clearance - Check
994H Wheel Loader Engine Supplement Pump Drive (Rear) from Engine - Separate
994H Wheel Loader Engine Supplement Pump Drive (Rear) to Engine - Connect
C7.1 Engines for Caterpillar Built Machines Fuel Manifold (ARD) - Remove and Install - Pilot Solenoid Only
D9T Track-Type Tractor Engine Supplement Air Cleaner - Remove and Install
C7.1 Engines for Caterpillar Built Machines Combustion Head - Remove and Install - Pilot Only System
C7.1 Engines for Caterpillar Built Machines Nozzle Heater Harness - Remove and Install - Heated Nozzle Connection