Sumitomo SH200-5 Fault Code 0336: Complete Diagnostic Guide

What is Sumitomo SH200-5 Fault Code 0336?

Fault Code 0336 on the Sumitomo SH200-5 excavator indicates a malfunction in the Engine Oil Pressure Sensor circuit, specifically a low voltage or open circuit condition detected by the Engine Control Module (ECM).

This code triggers when the ECM receives abnormally low voltage readings from the oil pressure sensor circuit, typically below 0.5 volts. The oil pressure monitoring system is critical for protecting the engine from catastrophic damage due to inadequate lubrication. On the SH200-5's diesel engine, maintaining proper oil pressure monitoring ensures the hydraulic pump drive and turbocharger receive adequate lubrication under heavy load conditions.

When this sensor circuit fails, the ECM cannot accurately monitor engine oil pressure, potentially masking dangerous low-pressure conditions that could lead to bearing failure or engine seizure.

Common Symptoms

• Oil pressure warning lamp illuminated continuously on the instrument cluster
• Engine derate mode activated, limiting RPM to approximately 1,200-1,500 to prevent damage
• Audible alarm sounding intermittently or continuously during operation
• Engine may enter limp mode, restricting hydraulic function performance
• Diagnostic display shows active fault code 0336 when scanned with service tool

Potential Causes

Sensor-Related Issues:

• Failed oil pressure sensor due to internal element degradation (common on machines with 6,000+ hours)
• Sensor diaphragm rupture from pressure spikes or contaminated oil

Wiring and Connector Problems:

• Harness chafing at known rub points near the engine block mount bracket
• Corroded or moisture-damaged connector pins at the sensor plug (3-pin connector)
• Broken signal wire between sensor and ECM, particularly at flex points near engine mounts

Electrical Issues:

• Poor ground connection at the sensor mounting point due to oil residue buildup
• ECM internal circuit failure (rare, but possible on high-hour used machines)

How to Troubleshoot and Fix Code 0336

Step 1: Visual Inspection Inspect the oil pressure sensor (located on the engine block's oil gallery) and its wiring harness for obvious damage. On used excavators, check for oil leaks around the sensor base, which indicates seal failure. Examine the 3-pin connector for corrosion, bent pins, or moisture intrusion—common on machines stored outdoors.

Step 2: Electrical Testing Using a digital multimeter, disconnect the sensor and measure resistance across the sensor terminals. Specifications typically range from 50-150 ohms at room temperature. Next, check the signal wire voltage at the harness connector with ignition on, engine off—you should read approximately 5 volts (reference voltage from ECM). A reading below 1 volt indicates an open circuit or damaged harness.

Step 3: Circuit Continuity Check Test continuity between the sensor connector and the ECM connector (usually located behind the operator cab). Resistance should be less than 5 ohms. Pay special attention to harness routing near the starter motor and fuel injection pump, where heat and vibration cause insulation breakdown on aged machines.

Step 4: Sensor Replacement and Verification If testing confirms sensor failure, replace with an OEM-equivalent oil pressure sensor (ensure pressure rating matches original specs). Before installation, clean the mounting threads and apply anti-seize compound. After replacement, clear the fault code using diagnostic software and perform an operational test under load to verify proper oil pressure readings (typically 40-60 PSI at operating temperature).

Disclaimer: This guide provides general diagnostic information. Always consult the Sumitomo SH200-5 service manual for exact specifications. If you're uncomfortable performing electrical diagnostics, seek assistance from a certified heavy equipment technician to prevent further damage to the machine's electrical system.