What is Sany General Fault Code P847?

Fault Code P847 indicates a malfunction in the hydraulic pump control system, specifically related to the pump solenoid valve circuit or its electrical feedback signal. This diagnostic trouble code (DTC) is triggered when the Electronic Control Module (ECM) detects an abnormal voltage, open circuit, or short circuit in the pump pressure control solenoid valve wiring or the valve itself.

In Sany excavators, the hydraulic pump control system is critical for regulating flow and pressure across all hydraulic functions. The pump solenoid valve modulates hydraulic output based on operator demand and load conditions. When Code P847 appears, the ECM cannot properly control pump displacement, which directly affects machine performance, fuel efficiency, and responsiveness. For used excavators, this fault often stems from electrical degradation rather than mechanical pump failure, making proper diagnosis essential before expensive component replacement.

Common Symptoms

• Reduced hydraulic power across all functions (boom, arm, bucket, swing)
• Illuminated warning light on the instrument cluster, often accompanied by an audible alarm
• Sluggish or erratic machine response to joystick inputs, particularly under load
• Engine derating or unusual RPM fluctuations as the ECM attempts to protect the hydraulic system
• Intermittent fault activation that may clear and return, especially when operating in wet or dusty conditions

Potential Causes

The most common technical causes for Code P847 on used Sany excavators include:

• Damaged or corroded wiring harness at known rub points near the pump mounting area or along the main chassis harness
• Failed pump solenoid valve due to internal coil breakdown, contamination, or wear from extended service hours
• Loose or corroded electrical connectors at the solenoid valve or ECM, particularly on machines exposed to harsh environments
• ECM internal fault or software corruption (less common but possible on older units)
• Hydraulic contamination causing mechanical binding of the solenoid spool, leading to electrical overcurrent

How to Troubleshoot and Fix Code P847

Step 1: Visual Inspection and Connector Check
Begin by inspecting the pump solenoid valve connector and associated wiring harness for visible damage, corrosion, or oil contamination. On used excavators, pay special attention to harness routing near moving components or sharp edges where insulation may have worn through. Clean all connector pins with electrical contact cleaner and ensure secure engagement.

Step 2: Electrical Testing with Multimeter
Disconnect the solenoid valve connector and measure coil resistance across the valve terminals (typically 10-25 ohms for Sany models—consult service manual for exact specification). Next, check for supply voltage at the harness connector with ignition on (should read battery voltage, approximately 12-14V). Test for ground continuity on the return circuit with less than 5 ohms resistance to chassis ground.

Step 3: Harness Continuity and ECM Testing
Using a multimeter or diagnostic software (such as Sany's proprietary PC-based diagnostic tool), perform a continuity test from the solenoid connector back to the ECM pins to identify any open circuits. Check for short circuits to ground or power by measuring resistance with all connectors disconnected. If wiring tests pass, the solenoid valve itself likely requires replacement.

Step 4: Component Replacement and System Verification
Replace the faulty component (typically the solenoid valve or damaged harness section). For used machines, always inspect hydraulic oil quality and replace filters if contamination is suspected, as debris can damage new solenoids. Clear fault codes using diagnostic software and perform a full operational test under load to verify proper pump response and confirm no code recurrence.

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Disclaimer: This guide provides general troubleshooting information for Code P847. Always consult the official Sany service manual for your specific model and serial number. If you lack proper diagnostic tools or experience with high-voltage electrical systems and hydraulics, consult a certified Sany technician or qualified heavy equipment mechanic to avoid injury or further machine damage.