The Fault Code section will provide clean, searchable code lists for agricultural and construction machinery.
Manufacturers Planned
- New Holland
- Case
- John Deere
- JCB
- Kubota
- Claas
- Massey Ferguson
- Deutz-Fahr
- Caterpillar
- Hitachi
- Kobelco
How the Fault-Code Pages Will Work
Each page will identify the code, system or controller where possible, give a plain-English description and link to related repair information or the appropriate workshop manual.
Important: fault codes can vary by model, controller and serial range, so machine identification should always be checked before diagnosis.
How to Read Tractor & Machinery Fault Codes
A practical guide to active and stored codes, SPN/FMI, sensor circuits, CAN communication, low-voltage faults, connectors, calibration and correct diagnostic procedure.
SPN/FMI & J1939 Fault Codes Explained
A practical reference to SPN numbers, FMI meanings, active and stored codes, occurrence counts, CAN communication, voltage faults and the correct diagnostic order.
CAN Bus & Communication Fault Codes
A practical guide to controller communication faults, CAN High/Low wiring, powers and earths, termination, intermittent network faults and diagnosing multiple codes correctly.
Sensor & Actuator Fault Codes – Open Circuit, Short to Ground & Signal Range
A practical guide to open circuits, short-to-ground and short-to-voltage faults, 5V reference supplies, sensor grounds, solenoids, PWM actuators and connector diagnosis.
DPF, EGR, AdBlue/DEF & Emissions Fault Codes Explained
A practical guide to DPF soot and ash, regeneration, EGR faults, SCR/DEF systems, NOx sensors, exhaust temperature sensors, derate and correct diagnostic procedure.
Fuel Rail Pressure, Injector & Common-Rail Fault Codes
A practical guide to low/high rail pressure, pressure sensors, metering valves, injector circuit faults, leak-off testing, fuel supply and safe common-rail diagnosis.
Transmission, Shuttle & PTO Fault Codes Explained
A practical guide to powershift and shuttle codes, clutch solenoids, speed sensors, pressure faults, calibration, interlocks, PTO engagement and limp mode.
Find a Machine-Specific Guide
Use the Workshop Guide Finder to narrow guides by manufacturer, model, problem or Workshop section.
Open Workshop Guide Finder