Diagnosing Pump 1 / Pump 2 Errors on a Fiat–Kobelco E215 Excavator

[MikePhua]

Understanding the Hydraulic Pumps and Error Context
The Fiat–Kobelco E215 is powered by dual hydraulic pumps—often operating in tandem to deliver fluid flow and pressure to essential hydraulic functions like boom swing, arm movement, and travel motors.
When the machine displays an error such as “Pump 1 / Pump 2,” it signals that one pump’s performance has deviated from expected parameters. This could stem from issues like pressure imbalance, sensor faults, or control system discrepancies.
Terminology You Should Know

• Hydraulic Pump – A mechanical device that converts engine power into fluid pressure for actuating hydraulic cylinders and motors.
  
• Load-Sensing System – An advanced circuit that modulates pump output based on demand, optimizing efficiency and power distribution.
  
• Pressure Sensor / Transducer – A device that relays real-time hydraulic pressure data to the control unit.
  
• ECU (Electronic Control Unit) – Manages pump operation, load sensing, and error detection across the hydraulic system.
  
• Proportional Valve – Adjusts fluid flow in fine increments, regulated by the control system for smooth machine responsiveness.
  

Possible Causes of Pump 1 / Pump 2 Error

• One pump under-performing—due to internal wear, cavitation, or damaged components.
  
• Faulty or misaligned pressure sensors leading to inaccurate readings.
  
• Hydraulic fluid that’s contaminated or at improper viscosity—affecting pump efficiency and pressure.
  
• ECU misinterpreting data due to wiring issues, sensor faults, or software glitches.
  
• Load-sensing inefficiency—imbalanced flow demand causing erratic pump loading.
  

Steps Toward Diagnosis and Resolution

• Conduct a visual inspection of hydraulic lines, fittings, and sensors. Check for leaks, kinks, or signs of physical damage.
  
• Monitor hydraulic pressure during pump operation to compare output from Pump 1 vs. Pump 2—look for notable discrepancies.
  
• Test or swap pressure sensors to rule out false readings causing the fault flag.
  
• Sample and assess hydraulic oil for contamination levels and correct viscosity.
  
• Scan and interpret ECU data logs for pump-specific error codes or diagnostic events.
  
• If mechanical issues persist, consult the manufacturer’s service manual for pump disassembly and rebuild, or consider professional servicing.
  

A Technician’s Story
A service technician once handled an E215 in a mining operation that frequently displayed a pump error at startup. Upon inspection, the error was traced not to the pump itself but to a tiny stone lodged in a suction line filter—starving Pump 1 of fluid briefly during startup. Cleaning the filter eliminated the error entirely. This experience reinforced that even minor hydraulic circuit obstructions can mimic major mechanical failures.
Industry Insight and Broader Context
Fiat–Kobelco excavators like the E215 are valued for their load-sensing hydraulics that improve fuel efficiency and response. Still, their complexity means that minor faults—dirty fluid, worn seals, or sensor drift—can trigger system alarms. As heavy-equipment maintenance becomes more preventive-data driven, technicians emphasize early detection of hydraulic issues through oil sampling, pressure logging, and ECU monitoring.
Benefits of Proper Troubleshooting

• Ensures hydraulic reliability and smooth operation under high-demand cycles.
  
• Prevents unnecessary component replacements, saving time and cost.
  
• Boosts operational safety by maintaining predictable system behavior.
  

Quick Reference: Diagnostic Checklist

• Inspect hydraulic lines and sensors visually.
  
• Measure and compare pump pressures under load.
  
• Validate sensor function—swap if needed.
  
• Check hydraulic oil condition and viscosity.
  
• Review ECU diagnostics for error trends.
  
• Clean suction filters and strainers thoroughly.
  
• Plan for pump rebuild or service if mechanical faults persist.
  

Final Thoughts
A “Pump 1 / Pump 2” error on the Fiat–Kobelco E215 often signals a hydraulic imbalance—but it doesn’t always point to a catastrophic failure. With structured diagnosis, careful inspection, and attention to fluid cleanliness and sensor accuracy, you can isolate and resolve the issue effectively—often without unnecessary overhauls. If you'd like help tracing wiring to sensors, identifying OEM part numbers, or setting up pressure logging, I’m happy to guide you further!