Garmin GHP Reactor Service Alert

Garmin has recently discovered a software issue on GHP Reactor autopilots. This issue may cause the autopilot to perform poorly, up to and including making the unit inoperative. In rare circumstances, the autopilot may behave unexpectedly, possibly performing abrupt maneuvers, although no such behavior related to this issue has been reported from installed systems.

Affected Products
GHP Reactor Autopilot units (SKUs listed):

010-00705-15 GHP Reactor Hydraulic Autopilot Corepack
010-00705-45 GHP Reactor Mechanical Autopilot Retrofit Corepack
010-00705-65 GHP Reactor Hydraulic with SmartPump Corepack
010-00705-71 GHP Reactor Hydraulic Autopilot Corepack for SmartPump
010-00705-80 GHP Reactor Steer-by-wire Standard Corepack
010-00705-81 GHP Reactor Steer-by-wire Corepack for Yamaha® Helm Master™
010-00705-82 GHP Reactor Steer-by-wire Corepack for Viking® VIPER®
010-00705-85 GHP Reactor Steer-by-wire Corepack for Volvo-Penta®
010-11052-60 Course Computer Unit, GHP Reactor Steer-by-wire
010-11052-61 Course Computer Unit, GHP Reactor Steer-by-wire for VIPER
010-11052-62 Course Computer Unit, GHP Reactor
010-11052-63 Course Computer Unit, GHP Reactor for Volvo-Penta
Note: The GHP Reactor model is shown on the NMEA 2000® devices settings menu on a connected GHC™ or GPSMAP® chartplotter.

A mandatory software update (v3.20) is currently available at no charge. This software update will correct possible performance issues and prevent the unit from becoming inoperative. Please update your GHP Reactor software as soon as possible, or bring your vessel to the dealer where you purchased your autopilot system for assistance with the software update. Your dealer was made aware of this update in Service Alert No. 1562.

As is best practice with any autopilot system, if any unexpected behavior occurs, disengage the GHP Reactor autopilot immediately. For installations in which a GPS device is used as the speed source, avoid using the autopilot in situations where there is a weak GPS signal.

To update the software, the GHP Reactor autopilot must be on a NMEA 2000 network connected to a Garmin GPSMAP with a card reader or to a NMEA 2000 Network Updater (010-11480-00).

Download the latest Marine Software Update Bundle for the GPSMAP Series with SD Card available on the Garmin website at This update bundle contains the GHP Reactor v3.20 software update.

Download the software update to an SD card following the instructions on the download page.

Update the autopilot software following the directions in the GPSMAP chartplotter manual or the NMEA 2000 Network Updater manual. If needed, you can download the latest manual for your device at

After the update is complete, go to the NMEA 2000 Devices settings menu and verify that the GHP Reactor software is at v3.20.