What is Komatsu PC210LC-7 Fault Code A000N2?

Fault Code A000N2 on the Komatsu PC210LC-7 indicates a communication error between the engine controller (ECM) and the pump controller (PMC) or loss of signal from the pump control system. This code specifically relates to the electronic communication network that manages the excavator's hydraulic pump output in response to engine load conditions.

The PC210LC-7 utilizes an advanced CLSS (Closed-Center Load Sensing System) that requires constant data exchange between the ECM (Engine Control Module) and PMC (Pump Control Module). When this communication fails or becomes intermittent, the machine cannot properly match hydraulic flow to operational demands. This is critical because the pump controller adjusts swash plate angles based on real-time engine data—without this communication, fuel efficiency drops dramatically and hydraulic performance becomes unpredictable.

Common Symptoms

When Code A000N2 is active, operators typically experience:

• Error message or warning lamp illuminated on the monitor panel (usually amber or red pump icon)
• Reduced hydraulic power across all functions—sluggish boom, arm, and swing movements
• Irregular engine response under load, with potential engine derating or hunting at idle
• Inconsistent attachment speed when operating under varying loads
• Occasional complete loss of hydraulic function if the system defaults to failsafe mode

Potential Causes

This fault code commonly appears on used excavators due to:

• Corroded or damaged wiring harness between ECM and PMC, particularly at connection points near the battery box and left-side engine compartment where harnesses are exposed to heat and vibration
• Failed PMC (Pump Control Module), often caused by moisture intrusion in older machines with compromised cab seals
• ECM communication port failure or internal ECM corruption from voltage spikes
• Loose or oxidized ground connections at the engine block or frame ground points
• Damaged CAN bus termination resistors causing signal reflection and data corruption
• Aftermarket monitor installations that inadvertently disrupted the CAN network

How to Troubleshoot and Fix Code A000N2

Step 1: Visual Harness Inspection Begin by thoroughly inspecting the wiring harness running from the ECM (located behind the operator's seat) to the PMC (mounted on the main pump). Look specifically for chafing points where harnesses contact frame rails, particularly near the swing joint. Check all connector pins for bent terminals, corrosion, or moisture. On used excavators, pay special attention to the grommets where harnesses pass through bulkheads—these often deteriorate and allow water ingress.

Step 2: Communication Testing with KOMTRAX or Diagnostic Software Connect Komatsu diagnostic software (or compatible scan tool) to the machine's diagnostic port. Monitor live data streams to verify whether the ECM is receiving data from the PMC. Check for CAN-H and CAN-L voltage levels—they should read approximately 2.5V at rest and oscillate between 1.5V-3.5V during communication. Use a multimeter to measure resistance between CAN-H and CAN-L terminals; it should read approximately 60 ohms with the key off, indicating proper termination resistors.

Step 3: Ground Circuit Verification Measure voltage drop across all ground connections while cranking the engine. Any reading above 0.2V indicates excessive resistance. Clean and tighten the primary engine ground (typically a braided strap from block to frame) and the ECM ground point. On machines with 5,000+ operating hours, consider replacing ground straps entirely, as internal corrosion is invisible but problematic.

Step 4: Component Isolation Testing If communication issues persist after harness repair, disconnect the PMC connector and measure power supply voltage (should be 24V with key on) and ground continuity. If power and ground are verified, the PMC itself may have failed—this is relatively common on used machines exposed to hydraulic oil mist and extreme temperatures. Before replacing the PMC (approximately $800-1,500), verify that the ECM can communicate with other modules to rule out ECM failure.

Step 5: Controller Replacement and System Reset After replacing any failed components, perform a system parameter reset using diagnostic software to clear adaptation values. Cycle the key off for at least 2 minutes to allow capacitors to discharge fully before restarting.

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Disclaimer: This guide provides general troubleshooting information for experienced diesel technicians. Always consult the official Komatsu service manual for your specific machine serial number and software version. Improper repairs to electronic control systems can cause additional damage. If unfamiliar with CAN bus diagnostics or high-voltage systems, seek assistance from a certified Komatsu technician.