Kobelco Excavator Error Code C023 – Meaning, Causes & Troubleshooting

Kobelco Excavator Error Code C023 – Meaning, Causes & Complete Troubleshooting Guide

Introduction

Modern Kobelco excavators rely heavily on electronic sensors to monitor hydraulic pressure and control machine performance. When a fault occurs in these sensors or their wiring, the machine shows an error code on the monitor.

One common issue faced by operators and technicians is Error Code C023.
In this article, we will explain:

• What Kobelco error code C023 means
• Which component is involved
• Symptoms you may notice
• Step-by-step troubleshooting
• How to fix the problem permanently

This guide is especially useful for Kobelco SK-8 / Super 8 series excavators.

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What Is Kobelco Error Code C023?

Error Code C023 on a Kobelco excavator indicates a:

Disconnection or open circuit in the P2 hydraulic pump pressure sensor

In simple words, the machine controller is not receiving a proper signal from the P2 pump pressure sensor.

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Which Component Is Related to C023?

The main component involved is:

• P2 Pump Pressure Sensor
  • Installed on the second hydraulic pump
  • Sends pressure feedback to the controller
  • Helps regulate hydraulic flow and machine load

If this signal is lost, the controller cannot correctly control hydraulic pressure.

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Common Symptoms of Error Code C023

When C023 appears, you may notice:

• ⚠️ Warning message or alarm on monitor
• 🐢 Excavator goes into safe mode / limp mode
• 💪 Weak hydraulic power
• 🕹 Slow or unresponsive boom, arm, or travel
• ⛔ Sudden reduction in machine performance

These symptoms protect the hydraulic system from damage.

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Main Causes of Kobelco C023 Error

1. Loose or Disconnected Sensor Connector

• Vibration causes connector to loosen
• Common after engine or pump service

2. Broken or Damaged Wiring Harness

• Wire cut near pump area
• Insulation damaged by heat or oil

3. Faulty P2 Pressure Sensor

• Internal sensor failure
• Incorrect voltage signal

4. Corroded Connector Pins

• Moisture or oil ingress
• Rusted or bent terminals

5. Controller Input Problem (Rare)

• ECU not reading sensor signal
• Usually checked last

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Step-by-Step Troubleshooting Guide for C023

Step 1: Locate the P2 Pressure Sensor

• Installed on hydraulic pump P2
• Follow hydraulic pump body to sensor port
• Identify wiring connector

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Step 2: Inspect Connector and Wiring

• Turn ignition OFF
• Remove sensor connector
• Check for:
  • Loose pins
  • Bent terminals
  • Oil or corrosion
• Clean connector if needed

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Step 3: Perform Wiring Continuity Test

Using a multimeter:

• Check continuity from sensor to controller
• Repair or replace damaged wires
• Perform wiggle test while checking signal

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Step 4: Check Sensor Voltage

Typical pressure sensor values:

• 5V reference supply
• Ground present
• Signal voltage varies with pressure

If no signal or incorrect voltage → sensor likely faulty.

What is multimeter?

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Step 5: Replace the P2 Pressure Sensor

• Install genuine or OEM-quality sensor
• Tighten to manufacturer torque
• Clear error code from monitor
• Restart machine and test operation

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Step 6: Check Controller (If Required)

Only if:

• Wiring and sensor are confirmed OK
• Error remains active

Controller issues are very rare compared to wiring or sensor faults.

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Can You Operate the Excavator With C023 Error?

⚠️ Not recommended

Operating with C023 may cause:

• Poor hydraulic control
• Overheating
• Damage to pump or valves

Always fix the error before long-term operation.

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Preventive Maintenance Tips

• Inspect pump sensor wiring during services
• Avoid pressure washing electrical connectors
• Secure harness away from sharp edges
• Use dielectric grease on connectors

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Item	Details
Error Code	C023
Machine	Kobelco Excavator
Fault Area	P2 Hydraulic Pump Pressure Sensor
Main Cause	Open circuit / disconnected signal
Common Fix	Wiring repair or sensor replacement

	Conclusion

Kobelco error code C023 is a common but easily fixable problem if diagnosed correctly.
In most cases, the issue is related to wiring or a faulty P2 pressure sensor, not the controller.

By following the step-by-step troubleshooting guide above, technicians can save time, reduce downtime, and avoid unnecessary part replacement.