Generac Generator 3717 Error Code Explained: Meaning, Causes & Fixes

 

Understanding and Resolving the Generac Generator 3717 Error

 

The 3717 error on a Generac generator is a common alert that indicates the generator has registered a service issue, most often relating to the controller’s ability to communicate with the generator (called “Loss of Communication with Controller”). Essentially, it means that the digital control panel and the main generator electronics are not talking to each other as they should. When you see the 3717 code, your generator may not run or may not perform automatic functions properly until the issue is addressed.

 

Immediate Steps to Safely Address the Error

 

• Safety First: Before working on the generator, make sure it is in ‘Off’ mode. Disconnect power to the unit by switching it off at the control panel and, if comfortable, switch off the main breaker for the unit as well. Avoid touching any wires or internal parts unless you are certain the power is disconnected.

 

Inspecting the Generator’s Connections

 

• Check Visible Connections: Open the generator enclosure. Look specifically at all visible wire plugs and connectors around the control board and the transfer switch area.
• Many times, the 3717 error is triggered by a loose, dirty, or corroded connector. Gently check that all communication cables and plugs (primarily the ones marked for the controller and generator communication) are firmly attached. Unplug these cables, inspect them for dirt, oxidation, moisture, or bent pins, then firmly reconnect.
• If you spot corrosion, clean with an electrical-safe contact cleaner and a small brush. If any connectors are extremely dirty or damaged, they may need professional replacement (especially true in areas with high humidity like St. Louis or heavy pollen in Nashville).

 

Troubleshooting the Controller and Cables

 

• Inspect Control Panel: Check the display panel for any signs of damage, water exposure, or error lights. If the control panel is unresponsive or the screen stays blank, the panel itself—or the relay board behind it—might be the source of the communication problem.
• Cable Integrity: The communication cable (also called a data or harness cable) runs between the controller and the main motherboard. Trace its path as best as you can for any abrasions, rodent damage, or kinks that might cause a break in communication.
• If you suspect cable damage but are unsure, you can gently wiggle the harness—a working connection shouldn’t cut out as you do this. If the screen flickers or the code resets, you likely have a faulty cable or connector.

 

Trying a Simple System Reset

 

• If after checking connections you find nothing obvious, attempt a basic reset:
  • Turn the generator to ‘OFF’ using the control panel.
  • Wait about 5 minutes for any charge to dissipate, then turn the generator’s main breaker (if equipped) off and back on.
  • Switch the generator back to ‘AUTO’ or ‘ON’ mode.
  • Observe if the error code disappears and if normal functions resume.
• If the code returns, the unit may require a deeper inspection.

 

When Professional Service is Needed

 

• If you’ve checked all the above and the 3717 error persists, the issue could be with the internal controller board, broken solder joints, or a failed sensor—these problems require specialized equipment and expertise to repair safely.
• For residents and businesses in St. Louis and Nashville, reaching out to a certified generator technician ensures compliance with safety standards and maintains your warranty.
• Never attempt to open sealed electronic modules yourself as this can cause further damage or void warranties.
• Explain to the technician the steps you took; this information helps speed up the diagnosis, especially for experienced service providers in St. Louis or Nashville.

 

Preventing Future 3717 Errors

 

• Schedule routine generator maintenance at least annually—this includes checking all electrical connections and cleaning out any debris, moisture, or pests that can interfere with sensitive wires.
• Ensure your generator housing is fully closed and weather-tight. St. Louis summers and Nashville storms can introduce humidity and debris that accelerate corrosion or short circuits.
• Avoid running the generator with open panels or while installing yard equipment nearby, which can increase risk of connection issues.

 

You can resolve the Generac 3717 error by first safely shutting down the generator, checking and resecuring all communication cables and connectors, inspecting the control panel and wiring for any visible issues, and performing a simple system reset. If these steps don’t clear the error, it’s important to contact a professional generator technician, especially in weather-prone regions like St. Louis and Nashville. Prevent future errors through regular maintenance, moisture control, and timely repairs. This careful approach will ensure your Generac generator reliably powers your home or business when you need it most.