Sany Excavator Fault Code A015: Complete Diagnostic Guide

What is Sany General Fault Code A015?

Fault Code A015 indicates a hydraulic pump solenoid control circuit malfunction in Sany excavators. This code typically signals that the Engine Control Module (ECM) has detected an abnormal voltage or current reading from the main hydraulic pump's proportional solenoid valve circuit.

This fault directly affects the load-sensing hydraulic system, which regulates pump displacement based on operator demand. The solenoid controls hydraulic flow and pressure by adjusting pump swash plate angle. When the ECM cannot properly communicate with or control this solenoid, the excavator's hydraulic performance becomes compromised, leading to reduced efficiency and potential protection mode activation.

For Sany machines, particularly older or high-hour units, this code is critical because improper hydraulic pump control can cause overheating, excessive fuel consumption, and premature component wear.

Common Symptoms

When Code A015 is active, operators typically experience:

• Erratic or sluggish hydraulic response across all functions (boom, stick, bucket, swing)
• Illuminated warning lamp on the instrument cluster, often accompanied by a fault code display
• Intermittent loss of hydraulic power, especially during combined operations
• Engine over-revving without corresponding hydraulic performance increase
• Machine entering derate mode or limiting maximum engine RPM to protect the system

Potential Causes

The most common technical causes for Code A015 in used Sany excavators include:

• Damaged or corroded wiring harness between the ECM and pump solenoid, particularly at harness routing points near the engine mount or pump assembly where vibration causes wire chafing
• Failed proportional solenoid valve on the main hydraulic pump due to internal coil breakdown or contaminated hydraulic oil causing valve sticking
• Broken or loose connector pins at the solenoid plug, common in machines operating in wet or muddy conditions
• ECM internal driver circuit failure, though less common than external wiring issues
• Low battery voltage or poor ground connections affecting solenoid control signal integrity

How to Troubleshoot and Fix Code A015

Step 1: Visual Inspection Begin by inspecting the wiring harness from the ECM to the hydraulic pump solenoid. Check for abraded insulation, pinched wires at mounting brackets, or damaged connectors. On used excavators, pay special attention to harness wear points where cables contact the frame during engine movement. Clean all connector pins and check for corrosion or bent terminals.

Step 2: Electrical Testing Using a digital multimeter, measure solenoid coil resistance. Typical specifications for Sany pump solenoids range from 8-15 ohms (consult your service manual). Disconnect the solenoid connector and check for continuity to ground—there should be none. With the ignition on, measure voltage at the harness connector; you should see approximately 12 volts. If voltage is absent, trace back toward the ECM for open circuits.

Step 3: Solenoid and Advanced Diagnostics If wiring checks pass, connect Sany diagnostic software (PC Suite or equivalent) to read live solenoid duty cycle data. Command the solenoid through the software while monitoring current draw. Excessive current (over 2 amps) or zero response indicates solenoid failure. For used machines, remove and bench-test the solenoid, checking for smooth plunger movement. Replace if sticky or if resistance values drift during temperature cycling.

Crucial for used excavators: Before replacing the solenoid (which can cost $300-600), thoroughly clean hydraulic oil filters and check oil condition. Contaminated oil can cause valve sticking that mimics electrical failure.

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Disclaimer: This guide provides general troubleshooting information. Always consult your Sany service manual for model-specific procedures and specifications. If you lack proper diagnostic tools or experience with high-voltage electrical systems, seek professional assistance from a certified heavy equipment technician.