What is Sumitomo SH350HD-6 Fault Code 7002?

Fault Code 7002 on the Sumitomo SH350HD-6 excavator indicates a malfunction in the hydraulic pump control system, specifically related to the pump flow control solenoid valve circuit. This code is triggered when the machine's Electronic Control Module (ECM) detects an abnormal voltage or resistance reading from the pump flow control solenoid, which regulates hydraulic oil flow to optimize performance and fuel efficiency.

This fault is critical for the SH350HD-6 because the hydraulic pump is the heart of all excavator functions. When the pump flow control solenoid malfunctions, the ECM cannot properly adjust hydraulic pressure based on operational demands. This results in reduced digging force, slower cycle times, and potential overheating of hydraulic components. For used excavators, this code often points to age-related electrical degradation or contamination in the hydraulic control circuits.

Common Symptoms

When Code 7002 is active on your Sumitomo SH350HD-6, you may experience:

• Reduced hydraulic power across all functions (boom, arm, bucket, swing)
• Warning light illumination on the instrument panel, often accompanied by an audible alarm
• Sluggish or inconsistent response when operating control levers
• Increased engine RPM without corresponding increases in hydraulic performance
• Intermittent loss of hydraulic functions, particularly during cold starts or after extended operation

Potential Causes

The most common technical reasons for Code 7002 on used SH350HD-6 excavators include:

• Failed pump flow control solenoid valve due to internal coil burnout or mechanical sticking from contaminated hydraulic oil
• Damaged wiring harness near the hydraulic pump mounting area, where vibration and heat cause insulation breakdown
• Corroded or loose electrical connectors at the solenoid valve, especially on machines operated in wet or corrosive environments
• ECM internal fault or corrupted programming (less common, but possible on high-hour machines)
• Low voltage supply to the solenoid circuit caused by failing alternator, poor ground connections, or degraded battery cables
• Contaminated hydraulic oil causing the solenoid spool to stick, creating electrical feedback

How to Troubleshoot and Fix Code 7002

Step 1: Visual Inspection Begin by locating the pump flow control solenoid valve on the main hydraulic pump (typically mounted on the pump's side housing). Inspect the electrical connector for corrosion, bent pins, or oil contamination. On used excavators, check the wiring harness for rubbing against the pump body or frame—this is a known wear point on the SH350HD-6.

Step 2: Electrical Testing Using a digital multimeter, disconnect the solenoid connector and measure resistance across the solenoid coil terminals. Typical specifications are 20-30 ohms at room temperature (consult your service manual for exact values). Next, check for supply voltage at the harness connector with the ignition on—you should read approximately 12-14 volts DC. If voltage is present but resistance is out of spec, the solenoid is faulty.

Step 3: Circuit and Ground Testing Check continuity between the solenoid ground wire and the machine's chassis ground. Measure resistance—it should be less than 1 ohm. For used machines, corrosion at ground points is common. Clean all ground connections with a wire brush and apply dielectric grease. Use Sumitomo diagnostic software (or compatible tools like Jaltest) to monitor real-time solenoid command signals from the ECM while operating the machine.

Step 4: Component Replacement and Verification If testing confirms solenoid failure, replace the pump flow control solenoid valve with a genuine Sumitomo part or high-quality aftermarket equivalent. Before installation, flush the hydraulic system and replace filters if the oil shows contamination. After replacement, clear the fault code using diagnostic software and perform a function test under load. Monitor for code recurrence over several operating hours.

Disclaimer: This guide provides general troubleshooting information for Sumitomo SH350HD-6 excavators. Hydraulic and electrical systems operate under high pressure and voltage. Always consult your machine's official service manual and consider professional diagnostic services for complex repairs, especially on used equipment with unknown maintenance history.