Sumitomo SH220LC-6 Fault Code 560: Complete Diagnostic Guide

What is Sumitomo SH220LC-6 Fault Code 560?

Fault Code 560 on the Sumitomo SH220LC-6 excavator indicates a malfunction in the engine control system's communication circuit, specifically related to the CAN (Controller Area Network) bus communication error between the engine ECU and the main controller. This diagnostic trouble code (DTC) signals that the engine control module (ECM) is unable to properly send or receive critical operational data through the electronic communication network.

This code is particularly critical for the SH220LC-6 because the CAN bus system coordinates all electronic functions between the engine, hydraulic systems, and operator interface. When communication breaks down, the machine may enter a protective derate mode or experience erratic performance, directly impacting productivity and potentially causing secondary system damage.

Common Symptoms

When Code 560 is active on your Sumitomo SH220LC-6, operators typically experience:

• Engine warning light illuminated on the instrument cluster with possible alarm buzzer activation
• Intermittent or complete loss of engine power, particularly noticeable during high-demand operations
• Erratic gauge readings including RPM, fuel level, or temperature displays showing incorrect or fluctuating values
• Hydraulic system performance inconsistencies due to improper engine-to-pump communication
• Machine may enter limp mode, restricting engine RPM to 1200-1500 range to prevent damage

Potential Causes

For used SH220LC-6 excavators, Code 560 typically stems from:

• Corroded or damaged CAN bus connectors at the ECM, main controller, or junction boxes (common failure point after 5,000+ operating hours)
• Broken or frayed CAN bus wiring harness, especially near engine mounting points where vibration causes conductor fatigue
• Water intrusion into the ECM or controller harnesses through deteriorated grommets or seals
• Faulty terminating resistors on the CAN bus network (120-ohm resistors at network endpoints)
• ECM internal failure or corrupted software, particularly in machines with electrical system history
• Loose or oxidized ground connections affecting the communication circuit reference voltage

How to Troubleshoot and Fix Code 560

Step 1: Visual Inspection Begin with a thorough examination of all wiring harnesses between the engine ECM (located near the fuel injection pump) and the main controller (cab-mounted). Look specifically for chafing points where harnesses contact the engine block, frame rails, or hydraulic lines. On used excavators, check all connector pins for green corrosion or pushed-back pins that prevent proper contact.

Step 2: CAN Bus Electrical Testing Using a digital multimeter, measure the resistance between the CAN-High and CAN-Low terminals at the ECM connector with the key off and all modules disconnected. You should read approximately 60 ohms (two 120-ohm terminating resistors in parallel). If readings show open circuit (infinite resistance) or short circuit (near zero ohms), locate the break or short in the network.

Step 3: Connector and Ground Verification Clean all CAN bus connectors with electrical contact cleaner and apply dielectric grease. Verify all ground points (particularly G101 and G103 grounds near the battery box) show less than 0.5 ohms resistance to chassis ground. For used machines, remove ground bolts, clean mating surfaces to bare metal, and reinstall with star washers.

Step 4: Advanced Diagnostics If basic checks pass, connect Sumitomo diagnostic software (or compatible heavy equipment scanner supporting J1939 protocol) to monitor real-time CAN bus traffic. Look for missing messages, corrupted data packets, or timing errors that indicate specific module failures requiring replacement.

Disclaimer: This guide provides general diagnostic procedures for Code 560. Due to the complexity of electronic control systems and variations in machine condition, always consult with a certified Sumitomo technician or qualified heavy equipment mechanic for definitive diagnosis and repair, especially when dealing with ECM replacement or software reprogramming.