Komatsu PC88 Dash Warning Lights: Symbols and Meanings

The Komatsu PC88 is a compact hydraulic excavator designed for versatility in urban construction and utility work. Its instrument cluster delivers essential system status and warning information to keep operators aware of machine health and performance. Understanding each indicator ensures safe and efficient operation of the PC88.

How to read the colors: Red lights signal immediate hazards requiring prompt shutdown or corrective action, while amber lights indicate cautionary issues needing attention soon. Green and blue lights typically show active systems or normal operation.

Komatsu PC88 Warning Light Symbols

SymbolNameColorWhat it meansWhat to do
Master Warning (Stop)REDA severe malfunction or critical system failure has been detected on the PC88, such as dangerously low oil pressure or engine overheating.Stop the machine immediately and investigate the source of the warning before resuming work.
Master CautionAMBERA non-critical fault or abnormal condition exists somewhere on the PC88, but the machine may still be operable.Review the monitor for specific warnings and address the cause at the next safe opportunity.
Check Engine (MIL)AMBERThe PC88's engine management system has detected a fault, which could affect performance or emissions.Check for diagnostic codes on the monitor and schedule inspection if the light persists.
Engine Oil PressureREDEngine oil pressure has dropped below safe limits on your PC88, risking severe engine damage.Shut down the engine immediately and check oil level and possible leaks.
Battery / ChargingREDThe alternator is not charging the battery properly, risking electrical system shutdown.Inspect the alternator belt and battery connections; do not continue work until resolved.
Coolant TemperatureREDEngine coolant temperature has exceeded safe limits, threatening engine overheating on the PC88.Stop the engine, allow it to cool, and check coolant level and radiator for issues.
Hydraulic SystemAMBERA problem has been detected in the PC88's hydraulic system, such as low pressure or filter clogging.Operate cautiously and check hydraulic fluid level and filters at the earliest opportunity.
Hydraulic OilAMBERHydraulic oil level or temperature is abnormal, which can impact the PC88's performance.Inspect hydraulic oil level and temperature; top up or allow cooling as needed.
Low FuelAMBERFuel level is low and the PC88 will soon require refueling to avoid interruption.Plan to refuel the excavator before the tank runs dry.
DPF / RegenerationAMBERThe diesel particulate filter on your PC88 needs regeneration to prevent engine derate.Follow the on-screen instructions to initiate or complete regeneration.
DEF / AdBlueAMBERDEF fluid level is low or there is a system fault, which can lead to reduced engine power.Refill DEF tank and check for system errors if warning persists.
Water in FuelAMBERWater contamination has been detected in the PC88's fuel system, risking injector or pump damage.Drain the water separator promptly to protect the fuel system.
Fuel Filter / Water SeparatorAMBERThe fuel filter is clogged or the water separator needs draining, impacting engine performance.Replace the filter or drain water as instructed in the operator’s manual.
Air FilterAMBERThe air filter restriction indicator is on, meaning the PC88's air filter is clogged.Inspect and clean or replace the air filter element.
Service / Hour MeterAMBERScheduled maintenance is due based on engine hours logged on the PC88.Arrange for required service tasks to maintain warranty and performance.
PParking BrakeREDThe parking brake is engaged, preventing the PC88 from moving.Release the parking brake before attempting to operate the excavator.
Work LightsBLUEThe work lights are currently switched on for nighttime or low-visibility operation.No action needed unless lights are not required.
Beacon / Rotating LightAMBERThe safety beacon is in operation, signaling that the PC88 is active on site.No action required unless beacon use is not needed.
Swing / Slew LockAMBERThe swing lock is engaged, restricting the PC88's upper structure from rotating.Disengage the swing lock to enable normal rotation.
Overload / CapacityREDThe PC88 has detected an overload condition, exceeding its rated lifting capacity.Reduce the load immediately to avoid machine instability or damage.

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

Most Important Warning Lights

Engine Oil Pressure

Common causes

  • Low engine oil level
  • Oil pump failure
  • Blocked oil filter

What to do

Immediately shut down the PC88, check oil level, and inspect for leaks or filter blockage before restarting.

Coolant Temperature

Common causes

  • Low coolant level
  • Radiator blockage
  • Failed cooling fan

What to do

Stop the engine, allow it to cool, and inspect coolant level and radiator for obstructions; repair any cooling system faults.

Battery / Charging

Common causes

  • Broken or loose alternator belt
  • Faulty alternator
  • Corroded battery terminals

What to do

Check the alternator belt and battery connections on the PC88; replace or repair defective components as needed.

Overload / Capacity

Common causes

  • Attempting to lift a load above rated capacity
  • Improper load distribution
  • Incorrect lifting configuration

What to do

Lower the load immediately and ensure future lifts stay within the PC88's rated limits; use proper lifting techniques.

Hydraulic System

Common causes

  • Low hydraulic fluid
  • Clogged hydraulic filter
  • Hydraulic leak

What to do

Inspect for leaks, check fluid level, and replace filters as needed to restore safe hydraulic function.

Frequently Asked Questions

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

Follow the instructions on the display to complete regeneration; avoid shutting down the engine until the process finishes.

How often should I check hydraulic oil on the PC88?

Check the hydraulic oil level daily before operation and top up as needed using the specified fluid.

Can I operate the PC88 if the Check Engine light is on?

You may continue to operate the machine if performance is normal, but schedule a diagnostic as soon as possible to prevent further issues.

Why does the water in fuel light turn on frequently?

Frequent activation suggests ongoing fuel contamination; regularly drain the water separator and inspect your fuel source.

What does the swing lock indicator mean?

It means the upper structure rotation is locked; disengage the swing lock before attempting to rotate the cab.