What is Komatsu PC200LC-8M0 Fault Code AB00KE?

Fault Code AB00KE indicates an abnormal signal or communication error in the hydraulic pump control system, specifically related to the pump flow control solenoid valve circuit. This code is triggered when the engine control module (ECM) detects an irregular voltage reading, open circuit, or short circuit in the solenoid valve that regulates hydraulic pump output on the Komatsu PC200LC-8M0 excavator.

This fault is critical because the hydraulic pump flow control directly affects machine performance, cycle times, and fuel efficiency. When AB00KE is active, the ECM may limit hydraulic output or enter a protective derate mode to prevent damage to the pump assembly or electrical components. On used excavators, this code often appears due to age-related wiring degradation or connector corrosion common in machines with 5,000+ operating hours.

Common Symptoms

• Hydraulic pump warning light illuminated on the instrument cluster or multi-monitor display
• Reduced hydraulic power or sluggish movement of boom, arm, or bucket cylinders
• Intermittent loss of auxiliary hydraulic functions (breaker or grapple circuits)
• Engine operating normally but with noticeable decrease in overall machine responsiveness
• Fault code stored in ECM memory, retrievable through Komatsu diagnostic software (KOMTRAX or PC-based tools)

Potential Causes

The most common technical reasons for AB00KE on used PC200LC-8M0 excavators include:

• Faulty pump flow control solenoid valve due to internal coil failure or mechanical sticking from contaminated hydraulic fluid
• Damaged wiring harness along the main frame rail where cables contact the chassis (known wear point on Dash-8 models)
• Corroded or loose connector terminals at the solenoid valve plug (exposed to moisture and debris near hydraulic tank)
• ECM internal fault or software corruption requiring reflashing (less common but possible in high-hour machines)
• Low system voltage from failing alternator or weak batteries affecting solenoid operation
• Previous improper repairs or aftermarket harness modifications causing resistance issues

How to Troubleshoot and Fix Code AB00KE

Step 1: Visual Inspection Locate the pump flow control solenoid valve mounted on the main hydraulic pump assembly. Inspect the electrical connector for oil contamination, bent pins, or corrosion. Check the wiring harness from the solenoid back to the ECM for chafing, particularly where it passes near the swing motor and hydraulic tank.

Step 2: Electrical Testing Using a digital multimeter, disconnect the solenoid connector and measure resistance across the solenoid coil terminals. Typical specification is 3-6 ohms at 20°C. Next, check for voltage supply at the harness connector with ignition on—should read approximately 12-14 volts. Any readings outside these ranges indicate solenoid failure or harness issues.

Step 3: Advanced Diagnostics Connect Komatsu diagnostic software to retrieve freeze frame data and monitor real-time solenoid command versus actual response. On used excavators, perform a "wiggle test" on connectors and harness while monitoring for intermittent faults—this reveals fractured wires inside insulation. Inspect ground connections at ECM and pump mounting points for corrosion.

Step 4: Repair or Replace Replace the solenoid valve if resistance is out of spec (Komatsu part number varies by serial range). Repair harness damage with proper gauge wire and heat-shrink connections. Clean all connectors with electrical contact cleaner and apply dielectric grease. Clear codes and perform operational test under load.

---

Disclaimer: This guide provides general troubleshooting information. Always consult the official Komatsu service manual for your specific serial number and seek professional assistance for complex electrical diagnostics or hydraulic system repairs.