What is Sumitomo SH210A6 Fault Code 1455?

Fault Code 1455 on the Sumitomo SH210A6 excavator indicates a malfunction in the hydraulic pump solenoid circuit, specifically related to abnormal voltage or current flow detected by the machine's Electronic Control Unit (ECU). This code typically signals an electrical fault within the pump control system that regulates hydraulic flow and pressure.

The hydraulic pump solenoid plays a critical role in modulating pump output based on load demands. When the ECU detects voltage irregularities outside manufacturer-specified parameters (typically 10-14 volts during operation), it triggers Code 1455 and logs the event. For the SH210A6, this is particularly important because the machine uses a sophisticated load-sensing hydraulic system that depends on precise electronic control. Ignoring this fault can lead to reduced hydraulic performance, increased fuel consumption, and potential damage to the pump control valve assembly.

Common Symptoms

Operators experiencing Code 1455 on their Sumitomo SH210A6 may notice:

• Warning light illuminated on the instrument cluster (typically hydraulic system or engine malfunction indicator)
• Reduced hydraulic power across all functions, with sluggish boom, arm, or bucket movements
• Intermittent loss of auxiliary hydraulic flow to attachments like breakers or grapples
• Engine RPM fluctuations when attempting heavy digging or lifting operations
• Inconsistent swing speed or hesitation during multi-function operations

Potential Causes

The most common technical reasons for Code 1455 on used SH210A6 excavators include:

• Damaged wiring harness near the hydraulic pump mounting area where vibration causes wire chafing (known weak point on this model)
• Failed pump solenoid coil due to heat exposure or internal short circuit (resistance should measure 20-30 ohms)
• Corroded electrical connectors at the pump solenoid, especially on machines operating in wet or corrosive environments
• ECU voltage supply issues from failing alternator or poor ground connections at the main wiring junction
• Shorted or open circuits in the solenoid control wiring between the ECU and pump assembly
• Internal ECU fault in older machines with high operating hours (less common but possible)

How to Troubleshoot and Fix Code 1455

Step 1: Initial Inspection Begin by visually inspecting the wiring harness running from the main ECU (located under the operator's cab) to the hydraulic pump solenoid. On used SH210A6 excavators, check for wire abrasion where the harness passes near the pump mounting bracket—this is a common failure point. Look for melted insulation, exposed copper, or signs of oil contamination on connectors.

Step 2: Electrical Testing Using a digital multimeter, disconnect the solenoid connector and measure coil resistance. The pump solenoid should read between 20-30 ohms at room temperature. Next, check for voltage supply at the connector with the ignition on—you should see battery voltage (12-14V). If voltage is present but the solenoid tests faulty, replacement is necessary. If no voltage is detected, trace the circuit back toward the ECU checking for breaks or shorts.

Step 3: Connector and Ground Verification Clean all electrical connectors with electrical contact cleaner and inspect for corrosion or bent pins. On used machines, corrosion inside weatherpack connectors is extremely common. Verify the ground connection at the pump mounting location—remove, clean with a wire brush, and reinstall with dielectric grease. Poor grounding causes 40% of electrical faults on older excavators.

Step 4: Advanced Diagnostics If basic checks don't resolve the issue, use Sumitomo diagnostic software (or compatible third-party tools) to monitor real-time solenoid current draw and voltage signals. Compare readings against factory specifications. The ECU should command 12V pulses to the solenoid during operation. Abnormal patterns may indicate an ECU internal fault requiring controller replacement or professional reprogramming.

Crucial for Used Equipment: Before replacing expensive components like solenoids or ECUs, thoroughly inspect all harness routing for wear points, verify all splice connections are intact, and measure voltage drop across the entire circuit under load conditions.

---

Disclaimer: This guide provides general troubleshooting information for educational purposes. Hydraulic and electrical systems can be dangerous. Always consult the official Sumitomo service manual for your specific machine serial number and consider professional diagnostic assistance for complex electrical faults.