What is Caterpillar Fault Code 2713-5?

Caterpillar fault code 2713-5 indicates a "Current Below Normal" condition in the Diesel Exhaust Fluid (DEF) Pump/Motor circuit. This diagnostic trouble code (DTC) is triggered when the Engine Control Module (ECM) detects that the electrical current flowing to the DEF pump motor is lower than the expected operating range during system operation.

This fault is critical because the DEF injection system is essential for reducing nitrogen oxide (NOx) emissions through Selective Catalytic Reduction (SCR) technology. When the DEF pump cannot operate properly due to insufficient current, the machine may enter derate mode to comply with emissions regulations, significantly impacting productivity and potentially causing complete engine shutdown if not addressed promptly.

Common Symptoms

• Amber or red warning light illuminated on the instrument cluster, specifically related to the aftertreatment system
• Engine power derate limiting machine performance to 50-75% of normal operating capacity
• DEF system malfunction messages displayed on the monitor screen
• Poor engine performance during high-load operations or failure to regenerate the diesel particulate filter (DPF)
• Countdown timer appearing on display, warning of impending severe derate or shutdown

Potential Causes

The most common technical reasons for code 2713-5 on used Caterpillar excavators include:

• DEF pump motor failure due to crystallized urea buildup or internal motor winding degradation
• Corroded or damaged wiring harness connections at the DEF pump connector, especially in machines exposed to harsh environments
• Poor electrical ground connection at the DEF tank or pump mounting location
• Blown fuse or faulty relay in the DEF pump power supply circuit
• ECM internal driver circuit failure preventing proper current delivery (less common but possible in high-hour machines)
• Damaged wiring near frame flex points or areas with known harness rub-through issues

How to Troubleshoot and Fix Code 2713-5

Step 1: Visual Inspection Begin by inspecting the DEF pump wiring harness for obvious damage, corrosion, or loose connections. On used excavators, pay special attention to connector pins for green corrosion or bent terminals. Check the DEF tank area for previous fluid leaks that may have damaged electrical components.

Step 2: Electrical Testing Using a digital multimeter, check for proper voltage supply at the DEF pump connector with the key on (should read battery voltage, typically 12-24V depending on machine model). Verify ground circuit continuity with resistance readings below 5 ohms. Disconnect the pump and measure motor winding resistance according to Caterpillar specifications (typically 2-8 ohms).

Step 3: Advanced Diagnostics Connect Caterpillar Electronic Technician (ET) diagnostic software to monitor live current draw during DEF pump activation. Compare actual current readings against specifications. Test the DEF pump relay and fuse in the power distribution module. If all electrical parameters check normal but the fault persists, the ECM driver circuit may require professional evaluation or ECM replacement.

Step 4: Component Replacement For used machines, consider that DEF pump assemblies often fail due to crystallization from old or contaminated DEF fluid. Before installing a new pump, flush the entire DEF system and install fresh, quality DEF fluid. Always apply dielectric grease to connectors during reassembly to prevent future corrosion.

---

Disclaimer: This guide provides general troubleshooting information. Always consult the official Caterpillar service manual for your specific machine model and serial number. If you're unfamiliar with electrical diagnostics or emissions systems, seek assistance from a certified Caterpillar technician to avoid costly misdiagnosis or safety hazards.