What is Sany Excavator Fault Code P967?

Fault Code P967 indicates a malfunction in the hydraulic pump solenoid control circuit, specifically detecting an abnormal voltage or current signal between the Electronic Control Module (ECM) and the proportional solenoid valve. This diagnostic trouble code (DTC) triggers when the ECM identifies that the electrical signal commanding the main hydraulic pump's displacement control is outside manufacturer-specified parameters, typically indicating an open circuit, short to ground, or excessive resistance.

This code is critical for Sany excavators because the proportional solenoid directly regulates hydraulic pump output based on operator demand. When this circuit fails, the machine loses precise control over hydraulic flow, resulting in compromised performance across all hydraulic functions including boom, stick, bucket, and swing operations.

Common Symptoms

• Reduced hydraulic power across all functions, with noticeably slower cycle times and weak digging force
• Erratic or unresponsive controls where joystick inputs don't produce expected hydraulic responses
• Warning light activation on the instrument cluster, often accompanied by audible alarms
• Engine derating or automatic speed reduction as the ECM enters protective mode
• Intermittent loss of hydraulic function that may temporarily restore after key cycles

Potential Causes

The most frequent causes of P967 in used Sany excavators include:

• Damaged wiring harness between the ECM and pump solenoid, particularly at flex points near the pump mounting area where vibration causes wire chafing
• Failed proportional solenoid valve due to internal coil breakdown, contamination, or normal wear after extended service hours
• Corroded or loose electrical connectors at the solenoid or ECM, especially common in machines operated in wet or corrosive environments
• ECM internal faults affecting the output driver circuit, though less common than external wiring issues
• Voltage supply problems including poor grounding points or battery connection issues affecting circuit integrity

How to Troubleshoot and Fix Code P967

Step 1: Visual Inspection Begin by inspecting the wiring harness running from the ECM to the hydraulic pump solenoid. On used excavators, check for wire insulation damage, connector corrosion, and proper connector seating. Pay special attention to harness routing near rotating components or sharp edges.

Step 2: Electrical Testing Using a digital multimeter, disconnect the solenoid connector and measure coil resistance (typically 8-15 ohms for Sany solenoids). Check for supply voltage at the connector with ignition on (should read approximately 12-24V depending on system design). Verify ground circuit continuity with less than 1 ohm resistance.

Step 3: Solenoid Function Test If electrical values are correct, perform a solenoid actuation test using Sany diagnostic software or a compatible scan tool. Command the solenoid through its full range while monitoring current draw. Replace the solenoid if it fails to respond or draws excessive current.

Step 4: Harness and ECM Verification For persistent codes after solenoid replacement, inspect the ECM connector pins for corrosion or damage. Test harness continuity between ECM and solenoid terminals. In used machines, consider that previous repairs may have introduced splice points that create resistance issues.

Disclaimer: This guide provides general troubleshooting information. Always consult factory service manuals and consider professional diagnostic assistance for complex electrical issues or if unfamiliar with high-voltage systems.