Kohler Generator HE Error Code Explained: Meaning, Causes & Fixes

 

How to Fix the HE Error on a Kohler Generator

 

When your Kohler generator shows an "HE" error code, it stands for "High Engine Temperature." This warning means the generator's engine is running hotter than it should, which can seriously damage the engine if ignored. The HE code will usually cause the generator to shut down as a safety measure. Here’s a step-by-step guide anyone in St Louis or Nashville can follow to troubleshoot and resolve the issue.

 

Understanding the Root Causes of the HE (High Engine Temperature) Error

 

Several things can cause high engine temperature:

• Low coolant level – The coolant keeps the engine at the right temperature. If it’s low, the engine overheats.
• Cooling system blockage – Leaves, dirt, or debris may block the air flow or coolant flow.
• Faulty radiator cap – A radiator cap that isn’t sealing properly allows coolant to escape or boil over.
• Malfunctioning thermostat – If the thermostat sticks closed, coolant can’t circulate.
• Broken cooling fan – The fan is vital for moving air to keep the engine cool.
• Coolant leak – If hoses or the radiator have holes, coolant leaks out, causing engine overheating.
• Sensor or wire failure – A faulty temperature sensor or a disconnected/corroded wire could falsely trigger the HE error.

 

What to Do Immediately When the HE Code Appears

 

• As soon as the generator displays the HE code, turn off the machine right away to prevent further damage.
• Allow the generator to cool for at least 30–60 minutes before opening any panels or inspecting it. The engine, radiator, and coolant can be extremely hot and can cause burns.

 

Step-by-Step Troubleshooting and Fixing the HE Error

 

• Check Coolant Level: Locate the generator’s coolant reservoir—this is usually a translucent tank near the radiator. Make sure the coolant level is between the "MIN" and "MAX" lines. If it’s low, add the recommended coolant type for your Kohler model, never plain water.
• Inspect for Visible Leaks: Look under the generator and around all coolant hoses, the radiator, and the engine block for any signs of wetness or dried coolant residue (which often appears as a colored stain or crust). Leaks should be repaired by tightening hose clamps or replacing damaged hoses.
• Clear Airflow Blockages: Remove any debris from the radiator, grille, or cooling fan. Make sure there’s nothing around the generator that blocks air from moving freely through the radiator, such as leaves or dust.
• Examine the Radiator Cap: When the engine is completely cool, carefully remove the radiator cap and check that the rubber seal is in good condition. Replace the cap if it looks cracked, hard, or doesn’t fit securely.
• Check the Cooling Fan: Turn the generator manually (or press the fan test button if equipped) and make sure the cooling fan spins freely without any obstruction or unusual noise. If the fan doesn’t spin, it may need to be repaired or replaced.
• Inspect the Thermostat: If comfortable, you can open the thermostat housing (when the engine is cold) to check if the thermostat appears stuck closed. However, thermostat replacement is typically a job for professionals serving areas like St Louis and Nashville.
• Check for Faulty Sensors or Wiring: Follow the wires from the temperature sensor to their connections. Look for frayed wires, loose plugs, or corrosion. A faulty sensor can trip the HE code even if temperatures are normal. If you suspect this, a full diagnosis from a technician may be needed.

 

If the Problem Persists

 

If after these steps your Kohler generator still shows the HE error or overheats, avoid further attempts to operate it. Continued overheating can cause serious internal engine damage. At this point:

• Contact a qualified generator service technician with experience in St Louis or Nashville.
• Provide them with your generator’s model and serial number, and explain the troubleshooting steps you have already tried.

A professional will inspect deeper causes such as water pump failure, radiator blockages inside the unit, internal engine issues, or advanced electrical faults.

 

Routine Maintenance to Prevent Future HE Errors

 

The best way to avoid the HE error is regular maintenance:

• Check coolant levels monthly and top off as needed.
• Have the coolant flushed and replaced based on your generator’s maintenance schedule (usually every 2–5 years).
• Keep the area around your generator clear of leaves, dirt, and debris.
• Schedule professional inspections annually, especially before storm or high-usage seasons.

If you’re in either St Louis or Nashville, local professionals can help with both emergency service and routine maintenance for residential and commercial Kohler generators.