What is Komatsu PC210-10 Fault Code DHSDMA?

Fault Code DHSDMA on the Komatsu PC210-10 excavator indicates a "Diesel Hydraulic System Data Mismatch/Malfunction Alarm," which signals a communication or data validation error between the engine Electronic Control Module (ECM) and the hydraulic system's main controller. This code appears when the machine's integrated control system detects inconsistent sensor readings or corrupted data transmission between the engine management and hydraulic load-sensing systems.

This fault is critical for the PC210-10 because Komatsu's intelligent Machine Control system relies on seamless data sharing between the diesel engine and hydraulic pump controllers to optimize fuel efficiency and power delivery. When this communication breaks down, the excavator may enter a protective derate mode or experience unpredictable hydraulic response.

Common Symptoms

• Warning light illumination on the instrument cluster with simultaneous error message on the monitor display
• Reduced engine power (derate mode) limiting maximum RPM to approximately 1,500-1,800 RPM
• Erratic hydraulic function response, particularly sluggish boom or swing operation under load
• Intermittent loss of fine control in combined hydraulic movements (simultaneous boom/swing operations)
• Increased fuel consumption due to ECM defaulting to non-optimized fuel maps

Potential Causes

The DHSDMA code on used PC210-10 machines typically stems from these technical issues:

• Corroded or loose connector pins on the CAN bus harness linking the ECM to the hydraulic controller (connector C210 behind the cab floor panel)
• Damaged communication wiring along the right-side main harness where it passes near the hydraulic tank mounting bracket—a known wear point
• ECM or hydraulic controller software mismatch after aftermarket ECM replacement or incomplete firmware updates
• Failing engine speed sensor or main pump pressure sensor sending corrupt analog signals
• Low system voltage issues (below 22V on 24V systems) caused by aging batteries or failing alternator

How to Troubleshoot and Fix Code DHSDMA

Step 1: Connect Komatsu KOMTRAX diagnostic software or compatible scan tool to retrieve freeze-frame data. Check for simultaneous codes that might indicate primary failures (pump pressure sensors, engine speed sensor faults).

Step 2: Physically inspect CAN bus connectors behind the operator's seat and at the ECM (located under the right-side floor panel). Look for green corrosion, bent pins, or moisture intrusion. Clean contacts with electrical contact cleaner and apply dielectric grease.

Step 3: Test CAN-High and CAN-Low circuit continuity between ECM pin 23/24 and hydraulic controller connector. Use a multimeter to verify 60-ohm termination resistance across the CAN pair with power off. Check for shorts to ground.

Step 4: Verify battery voltage under load (engine running at high idle). Voltage should remain above 26V. On used excavators, weak batteries often cause intermittent communication errors.

Step 5: Check harness routing along the hydraulic tank bracket. This wear point frequently causes intermittent wire damage on machines with 4,000+ hours. Re-route and secure with proper clamps if chafing is visible.

Step 6: Perform ECM/controller software verification using KOMTRAX. Mismatched software versions between controllers require dealer-level reprogramming to synchronize communication protocols.

Disclaimer: This guide provides general troubleshooting information. Always consult the official Komatsu service manual for your specific machine serial number, and consider professional diagnosis for complex electrical issues involving controller programming.