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Troubleshooting a Reactor 40 Autopilot
Troubleshooting a ReactorTM 40 Autopilot can typically be narrowed down to a few areas.
NOTE: This FAQ is designed to provide a user with the ability to research & troubleshoot the autopilot system. Every boat is different and the particular problem may not be addressed in this FAQ.
NOTE: If more research is required, go to Marine Support Center.
NOTE: Always refer to the Reactor 40 Autopilot system and associated devices Owners Manuals for specific information and direction.
Check the NMEA 2000 Device List
Is the GHCTM autopilot controller and the Reactor 40 appearing on the NMEA 2000 device list? If it is not listed verify NMEA 2000 power and check all the connections on the NMEA 2000 network to the chartplotter or the GHC and Reactor 40 CCU, see the Technical Reference for Garmin NMEA 200 Products to identify the NMEA 2000 components and networking.
Is the Garmin Reactor 40 Autopilot software current?
If the software has never been updated or has not been updated in a long time update the software and then check the system, see Garmin Marine Device Software Updates for software update instructions.
Troubleshooting FAQs
Fatal Errors on a GHP 10 Autopilot
"Lost ECU" or "Lost Autopilot" Appearing on a GHP 10 Autopilot
GHP Autopilot Display (GHC) Warnings
Searching for Autopilot Controller
Blink Codes on a Garmin Autopilot ECU and CCU
Boat Icon Facing the Wrong Direction When Using a Garmin Autopilot
Autopilot Won't Stay on Course When Following a Route
Alternate Autotune on a GHP Reactor Autopilot
Autopilot Not Steering in a Straight Line
Accessing Dealer Mode on a Garmin Autopilot
"Lock to Lock" Value Requested During the Dockside Setup Wizard
Lock to Lock Test Fails on the Garmin Marine Autopilot System with SmartPump
Preserving Battery Life on a GHC Autopilot Remote
Recommended Speed During the Autotune Procedure
Tips for Bleeding the Hydraulic System
GHP 12 / Reactor Mechanical Autopilot Rudder Feedback Compatibility
Installation of a VDO rudder feedback sensor to compatible GHP autopilots
Using a Third Party Rudder Reference Sensor with GHP Autopilots Utilizing the SmartPump
Installing a SmartPump vertically
Diodes for the Garmin GHP 12 Solenoid Steering System
Mounting and Installation FAQs
The Reactor 40 CCU can be influenced by Electromagnetic Interference (EMI). For best results, the CCU should be at least 3 feet away from magnetic materials (speakers, ferrous metal, pumps), power cables, batteries and any other EMI producing items. Failure to follow these guidelines will prevent the autopilot from functioning properly. When in doubt, refer to the CCU Mounting and Connection Considerations in the autopilot installation instructions. The Reactor 40 Autopilot should be mounted in close proximity to the vessels pivot point, and as close to the waterline and centerline as possible. The CCU can be mounted in any orientation. For best results Garmin recommends the Reactor 40 CCU cable connections are pointed toward the bow and mounted horizontally (the top of the CCU "Garmin" faces upward).
Shadowdrive mounting considerations
Difficulty Steering After Installing Shadow Drive and Shadow Drive Fittings: Normal and Verado
The Shadow Drive of the GHP 10 Autopilot isn't disengaging properly
GHP Autopilot Installation Without a Shadow Drive
The purpose of a Shadow Drive on an Autopilot
Using Teflon tape to seal the hydraulic fittings of a Garmin Marine Autopilot
GHC and using a 7-Pin Data Cable
What Happens if the Red Wire is Connected on the GHC 20 When Using the 7-pin cable?
Always refer to the Installation, Configuration and Owners Manuals for specific information and guidance.
If there are additional Autopilot specific questions, contact Garmin Marine Product Support.
Getting Started FAQs
Getting Started with a Garmin Reactor 40 Autopilot
Selecting a Garmin Reactor 40 Autopilot
Commissioning a Garmin Reactor 40 Autopilot
What are the Components of a Garmin Reactor 40 Autopilot