What is Sany Excavator Fault Code P244?

Fault Code P244 indicates a malfunction in the hydraulic pump solenoid control circuit, specifically detecting an abnormal voltage or open circuit condition in the pump control system. This diagnostic trouble code (DTC) is generated when the Electronic Control Module (ECM) detects that the signal voltage to the hydraulic pump proportional solenoid valve falls outside the manufacturer's specified range, typically between 0.5-4.5 volts.

This code is critical for Sany excavators because the hydraulic pump solenoid directly regulates hydraulic flow and pressure throughout the machine. When this circuit malfunctions, the ECM cannot properly modulate pump output based on operator demand, leading to compromised performance and potential component damage. On used machines, this fault often results from degraded wiring harnesses or contaminated electrical connections rather than actual solenoid failure.

Common Symptoms

• Reduced hydraulic power across all functions (boom, arm, bucket, swing) or complete loss of hydraulic response
• Engine RPM fluctuations or inability to maintain consistent operating speed under load
• Warning light illumination on the instrument cluster, often accompanied by an audible alarm
• Limp mode activation where the machine operates at significantly reduced capacity to prevent further damage
• Erratic hydraulic response with delayed or jerky movements during operation

Potential Causes

The most common causes of P244 on used Sany excavators include:

• Damaged or corroded wiring harness between the ECM and hydraulic pump solenoid, particularly at rub points near the pump mounting area
• Failed hydraulic pump proportional solenoid valve due to internal coil breakdown or mechanical seizure from contamination
• Corroded or loose electrical connectors at the solenoid or ECM, especially on machines exposed to harsh environments
• ECM internal circuit failure affecting the solenoid driver circuit (less common but possible on higher-hour machines)
• Voltage supply issues from the main power harness, including poor ground connections or damaged relay contacts
• Contaminated hydraulic oil causing solenoid valve sticking, which increases electrical current draw and triggers the fault

How to Troubleshoot and Fix Code P244

Step 1: Visual Inspection Begin by thoroughly inspecting the wiring harness from the ECM to the hydraulic pump solenoid. On used excavators, check for harness chafing against the pump housing, frame members, or hydraulic lines. Examine all connector pins for corrosion, bent terminals, or oil contamination. Clean connectors with electrical contact cleaner and apply dielectric grease.

Step 2: Electrical Testing Using a digital multimeter, disconnect the solenoid connector and measure resistance across the solenoid coil terminals (typical specification: 8-15 ohms). Then check for supply voltage at the harness connector with ignition on (should read battery voltage, approximately 12-14V). Measure signal voltage from the ECM during operation using manufacturer-specific diagnostic software like Sany PC-E or compatible scan tools.

Step 3: Component Testing and Replacement If voltage and resistance readings are within specification, perform a dynamic test by commanding the solenoid through diagnostic software while monitoring current draw (typical: 0.8-1.5 amps). For used machines, replace the hydraulic oil filter and check oil cleanliness, as contamination frequently causes solenoid valve sticking. If harness damage is evident at known wear points, repair or replace the affected section with properly routed and secured wiring. Replace the solenoid valve only after confirming electrical circuit integrity.

Disclaimer: This guide provides general troubleshooting information. Always consult the manufacturer's service manual for your specific machine model and serial number. Complex electrical diagnostics should be performed by qualified technicians with proper equipment. Improper repairs may cause additional damage or safety hazards.