Diagnosing No-Start Condition on the 2007 New Holland L185

[MikePhua]

Cranking Without Ignition
The New Holland L185 skid steer loader, introduced in the mid-2000s, was designed for compact power and versatility across construction, agriculture, and landscaping. Built by CNH Industrial, the L185 featured a 60 hp turbocharged diesel engine, hydrostatic drive, and a robust electrical system. With thousands of units sold across North America and Europe, it remains a popular choice for operators seeking reliability in tight spaces.
One recurring issue with aging L185 units is a no-start condition where the engine cranks but fails to ignite. In a documented case, the machine showed no smoke during cranking and lacked power at the fuel shutoff solenoid. When power was manually applied to the solenoid, the engine started and ran normally—suggesting an electrical fault rather than a mechanical one.
Terminology Notes

• Fuel Shutoff Solenoid: An electrically actuated valve that controls fuel flow to the injection pump. Without power, it remains closed.
  
• Cranking: The rotation of the engine by the starter motor, prior to combustion.
  
• ECU (Engine Control Unit): The onboard computer that manages ignition, fuel delivery, and safety interlocks.
  
• Safety Interlocks: Systems that prevent engine start unless certain conditions are met, such as seat occupancy or parking brake engagement.
  

Initial Observations and Clues

• Dash lights illuminate correctly before cranking.
  
• Oil pressure warning activates after cranking, likely due to the ECU expecting engine operation.
  
• No smoke from the exhaust, indicating no fuel delivery.
  
• Manual power to the solenoid restores normal function.
  

These signs point to a failure in the power delivery circuit to the fuel solenoid, possibly caused by a faulty relay, broken wire, or ECU miscommunication.
Troubleshooting Strategy

• Check Solenoid Voltage: Use a multimeter to measure voltage at the solenoid during key-on and cranking. If zero, trace upstream.
  
• Inspect Relays and Fuses: Locate the fuel solenoid relay and test for continuity. Replace if corroded or non-functional.
  
• Verify Safety Interlocks: Ensure seat switch, seatbelt sensor, and parking brake switch are functioning. A failed interlock may block solenoid activation.
  
• Test ECU Output: If all inputs are valid, the ECU should send power to the solenoid. If not, the ECU may be faulty or require reprogramming.
  
• Bypass Test: Temporarily bypass the solenoid circuit with a fused jumper to confirm engine operation. Do not use as a permanent fix.
  

Operator Anecdotes and Field Wisdom
One technician in Wisconsin shared that his L185 had a similar issue caused by a broken wire under the seat. After repairing the harness, the solenoid received power and the machine started reliably. Another operator in Quebec discovered that his fuel solenoid relay had failed due to moisture ingress. Replacing the relay resolved the issue instantly.
A contractor in Texas noted that his L185 would crank but not start during cold mornings. After installing a battery warmer and cleaning the ground connections, the problem disappeared—highlighting the importance of electrical integrity in low temperatures.
Preventive Measures and Long-Term Solutions

• Seal Electrical Connectors: Use dielectric grease to prevent corrosion in relays and plugs.
  
• Inspect Wiring Harnesses Quarterly: Look for abrasion, rodent damage, or loose connectors.
  
• Replace Aging Relays Proactively: After 2,000 hours, relays may degrade and cause intermittent faults.
  
• Update ECU Firmware: Some models benefit from software updates that improve fault tolerance.
  
• Install Diagnostic Port Adapter: Allows quick access to ECU data and fault codes.
  

Machine History and Market Impact
The L185 was part of New Holland’s 100-series skid steers, which saw strong sales in North America between 2005 and 2010. Known for their lift capacity and compact footprint, these machines were widely adopted by rental fleets and small contractors. CNH Industrial continues to support legacy models through its dealer network and aftermarket suppliers.
Conclusion
A 2007 New Holland L185 that cranks but won’t start is likely suffering from an electrical fault in the fuel solenoid circuit. By methodically testing relays, safety switches, and ECU outputs, operators can pinpoint the issue and restore functionality. With proper maintenance and attention to electrical systems, the L185 remains a dependable asset in the field.