Applicable Systems
PC200 Excavator
Symptoms
Hydraulic pilot pressure below operating range; joystick control response reduced; pilot filter may be clogged.
Possible Causes
- Pilot hydraulic pump worn
- Pilot oil filter clogged
- Pilot relief valve stuck open
Troubleshooting Steps
- Step 1: Check pilot pressure at test port (should be 30-40 bar)
Pressure within spec - Step 2: Inspect pilot oil filter element
Filter clean - Step 3: Check pilot pump output
Pump output adequate - Step 4: Test pilot relief valve
Valve seats properly - Step 5: Replace filter or pump as needed
Pilot pressure restored
How to Reset
Clear via service monitor after pilot system service.
Common Replacement Parts
- Pilot Oil Filter P/N: 705-99-67110
Frequently Asked Questions
- Q: What is hydraulic pilot pressure?
Low-pressure hydraulic signal from joysticks that controls main hydraulic valve spools. Allows precise proportional control with low operator effort.
Source: truckmanualshub.com Komatsu PDF
Category: Heavy Equipment