Kubota Excavator L3901 Dashboard Symbols and Warning Lights Explained

The Kubota L3901 is a compact tractor designed for versatility and reliability in demanding agricultural and construction environments. Its instrument cluster provides operators with essential status and warning indicators to ensure optimal performance and safety during operation.

How to read the colors: Red lights signal immediate attention is needed—often indicating a system failure or potential damage. Amber lights warn of issues requiring prompt action, while green and blue lights typically indicate normal system operation or active features.

Kubota Excavator L3901 Warning Light Symbols

SymbolNameColorWhat it meansWhat to do
Master Warning (Stop)REDA critical fault has been detected in a major system of the L3901, requiring the tractor to be stopped immediately.Safely shut down the engine and inspect for visible issues or consult a Kubota technician.
Check Engine (MIL)AMBERThe engine control system has detected a malfunction affecting performance or emissions on your L3901.Continue operating at reduced load and schedule a diagnostic check with your Kubota dealer.
Engine Oil PressureREDEngine oil pressure has dropped below safe levels, risking severe engine damage if operation continues.Stop the engine immediately and check oil level and for leaks; do not restart until resolved.
Battery / ChargingREDThe alternator is not charging the battery, which will eventually lead to engine shutdown on the L3901.Check the alternator belt and electrical connections; seek service if the light remains on.
Coolant TemperatureREDEngine coolant temperature is too high, indicating possible overheating in the L3901's engine.Stop operation, let the engine cool, and inspect coolant levels and radiator for blockages.
Low FuelAMBERThe fuel tank of your L3901 is nearly empty, risking engine stalling if not refueled soon.Refuel the tractor at the next opportunity to avoid interruptions.
Glow Plug / PreheatAMBERThe glow plugs are active, preheating the combustion chamber for easier cold starting on the L3901.Wait for the light to turn off before starting the engine in cold conditions.
DPF / RegenerationAMBERThe diesel particulate filter on your L3901 requires regeneration to burn off soot buildup.Continue operating at higher RPM or initiate a parked regen as per the operator's manual.
DEF / AdBlueAMBERThe DEF fluid level is low in the L3901, which could reduce engine power if ignored.Top up the DEF tank promptly to maintain emissions compliance and avoid power loss.
Water in FuelAMBERThe water separator has detected water contamination in the fuel system of your L3901.Drain the water separator to prevent injection system damage.
Hydraulic OilREDHydraulic oil pressure or level is critically low, risking loss of implement control on the L3901.Stop operation, check hydraulic fluid level, and inspect for leaks before resuming work.
Fuel Filter / Water SeparatorAMBERFuel filter is clogged or water separator is full, affecting fuel delivery to the L3901's engine.Replace the filter and drain the separator as soon as possible.
Service / Hour MeterAMBERScheduled maintenance is due based on the accumulated operating hours for your L3901.Perform maintenance tasks per the service interval chart in the operator's manual.
Work LightsBLUEThe auxiliary work lights are switched on to illuminate the work area during L3901 operation.Switch off the work lights when not needed to conserve battery power.
PParking BrakeREDThe parking brake is engaged, preventing movement of the L3901.Release the parking brake before attempting to drive.

15 symbols shown. Icons follow ISO 2575 dashboard standards; exact graphics vary by model year.

Most Important Warning Lights

Engine Oil Pressure

Common causes

  • Insufficient oil level in the crankcase
  • Oil pump malfunction
  • Blocked oil filter

What to do

Shut off the engine immediately, check the oil level, and inspect for leaks or filter blockages. Only restart the L3901 once oil pressure is restored.

Coolant Temperature

Common causes

  • Low coolant level
  • Radiator blockage
  • Thermostat failure

What to do

Allow the engine to cool, then check coolant level and inspect the radiator for obstructions. Address any leaks or faults before operating the L3901 again.

Hydraulic Oil

Common causes

  • Hydraulic fluid leak
  • Low reservoir level
  • Damaged hydraulic hoses

What to do

Stop the tractor, check the hydraulic oil level, and inspect hoses and connections for leaks. Refill fluid and repair any damaged parts before resuming work.

Battery / Charging

Common causes

  • Loose or corroded battery terminals
  • Drive belt failure
  • Alternator malfunction

What to do

Check and clean battery terminals, inspect the alternator drive belt, and test alternator output. Replace or repair faulty components to restore charging.

Frequently Asked Questions

What should I do if the DPF regeneration light stays on?

Operate the L3901 at higher RPMs for a period to allow automatic regeneration, or follow the manual procedure for a parked regen if the light does not clear.

Why does my L3901 show the glow plug light even in warm weather?

The glow plug system may activate briefly during all starts to ensure smooth ignition, regardless of ambient temperature.

How often should I check the hydraulic oil level?

Inspect the hydraulic oil level before each use, especially if operating attachments or after noticing slow or erratic implement movement.

Can I continue to operate with the low fuel light on?

You should refuel as soon as possible; running out of fuel can introduce air into the fuel system, making restarting difficult.

What does the water in fuel indicator mean?

It signals that the water separator has collected water; drain it promptly to prevent damage to the injection system.