What is Komatsu PC100-6 Fault Code E317?

Fault Code E317 indicates a malfunction in the hydraulic pump control system, specifically related to the pump solenoid valve circuit or its signal feedback loop. This code typically triggers when the Electronic Control Module (ECM) detects abnormal voltage, resistance, or communication issues with the pump control solenoid, which regulates hydraulic flow and pressure based on operational demand.

On the PC100-6, this system is critical because it directly affects load-sensing hydraulic performance. When E317 activates, the machine may lose optimal hydraulic efficiency, leading to sluggish operation or even automatic derate to protect the hydraulic system from damage.

Common Symptoms

• Reduced hydraulic response: Slow or weak boom, arm, or bucket movements despite normal engine RPM
• Intermittent loss of hydraulic power: Occasional complete hydraulic failure followed by normal operation
• Error indicator illuminated: Service or hydraulic warning light on the dashboard remains steady or flashes
• Unusual hydraulic pump noise: Whining or cavitation sounds indicating improper pressure regulation
• Machine enters reduced power mode: ECM limits engine output to prevent hydraulic system damage

Potential Causes

The most common technical causes for E317 on used PC100-6 excavators include:

• Faulty pump control solenoid valve: Internal coil failure or mechanical sticking due to contaminated hydraulic fluid
• Damaged wiring harness: Wire chafing at pivot points near the pump mounting area (known wear point on this model)
• Corroded or loose electrical connectors: Moisture intrusion at the solenoid connector causing high resistance
• ECM voltage supply issues: Failed relay or poor ground connection affecting the solenoid circuit
• Contaminated hydraulic oil: Metal particles or debris interfering with solenoid valve operation

How to Troubleshoot and Fix Code E317

Step 1: Using Komatsu diagnostic software (or compatible scan tool), verify the code is current and check freeze frame data for voltage readings during fault occurrence. Normal solenoid voltage should read 12-14V DC.

Step 2: Physically inspect the pump solenoid connector for corrosion, bent pins, or moisture. On used excavators, this connector often accumulates debris. Clean with electrical contact cleaner and apply dielectric grease.

Step 3: With the solenoid connector disconnected, use a multimeter to check solenoid coil resistance. Specification is typically 10-15 ohms. Readings below 5 ohms or above 20 ohms indicate solenoid replacement is necessary.

Step 4: Inspect the wiring harness from the ECM to the solenoid, paying special attention to areas where the harness passes near the pump or engine block. Look for insulation wear, broken wires, or signs of heat damage.

Step 5: Check hydraulic oil quality and pressure. Change contaminated oil and filter before replacing electrical components, as debris often causes mechanical valve sticking rather than electrical failure.

Disclaimer: This guide provides general troubleshooting steps. Always consult qualified diesel mechanics or Komatsu-certified technicians for complex diagnostics and repairs, especially regarding hydraulic system work.