Overview

The Garmin Reactor 40 Steer-by-Wire Standard Corepack is a below-deck autopilot package for steer-by-wire steering systems, built around a solid-state 9-axis AHRS course computer unit (CCU). The CCU is IPX7-rated, connects over NMEA 2000, and uses a 9 to 16 Vdc NMEA 2000 power input; the CCU body measures 91.4 mm (3 19/32 in.) in diameter.

This corepack is intended for SeaStar Optimus systems, Yanmar Marine ZT 370 stern drive electronic power steering systems, and ZF 2800 Pod drives. It supports both powerboat and sailing functions, including heading hold and step turns, plus wind hold and tack/jibe when paired with a wind sensor on the NMEA 2000 network.

Key features

• Compatible steer-by-wire support for SeaStar Optimus, Yanmar Marine ZT 370, and ZF 2800 Pod drives.
• Solid-state 9-axis AHRS CCU can be mounted in any orientation in a non-submerged location near the boat’s center.
• NMEA 2000 network connection for control and data sharing; NMEA 2000 power input is 9 to 16 Vdc (LEN 3 / 150 mA).
• CCU housing is IPX7-rated and uses a 3 m (9.5 ft) CCU cable that must not be cut.
• Supports up to 3 GHC helm control units on the same NMEA 2000 network.
• Audible buzzer/alarm included for autopilot alerts at the helm.
• Includes NMEA 2000 connection parts to build a basic network when the boat does not already have one.

Variants

This corepack is offered in multiple configurations based on the helm control option included with the package.

Each configuration includes the Reactor 40 CCU, CCU cable, buzzer, and the NMEA 2000 cabling/connectors listed below. The main difference is whether a dedicated GHC autopilot instrument is included, or whether setup and control are handled from a compatible Garmin chartplotter on the same NMEA 2000 network.

• 010-00705-86: Includes GHC 20 autopilot helm control display. The 4-inch color display gives a dedicated autopilot interface at the helm.
• 010-02794-03: Includes GHC 50 autopilot instrument. The 5-inch touchscreen adds a larger, modern control surface for autopilot operation.
• 010-00705-90: No dedicated autopilot instrument included. Configuration and control are performed through a compatible Garmin chartplotter connected to the same NMEA 2000 network as the CCU.

What’s included

• Reactor 40 CCU (Course Computer Unit)
• CCU cable
• Buzzer/alarm
• NMEA 2000 drop cables (2 meters)
• NMEA 2000 power cable
• NMEA 2000 T-connectors
• Male and female terminators
• Documentation

Compatibility and fit

This package is for boats with steer-by-wire steering hardware, not for mechanical cable steering and not for standard hydraulic pump drives. Confirm the steering system model on the boat (for example SeaStar Optimus, Yanmar Marine ZT 370, or ZF 2800 Pod drives) and verify you have a place below decks to mount the CCU close to the vessel’s center of rotation.

Installation and setup

The CCU should be mounted on a rigid surface in a non-submerged space and kept away from magnetic interference. A handheld compass is a practical way to check the chosen location before drilling, and stainless or brass mounting hardware should be used when substitutes are needed. The CCU cable is 3 m (9 ft) and must not be cut, so cable routing and component placement matter before anything is fastened down.

Plan the network and power side early. The CCU and helm control (if included) connect to a NMEA 2000 network using T-connectors; if you are building a new NMEA 2000 network, the NMEA 2000 power cable must be connected to a 9 to 16 Vdc source and is commonly switched so the network does not drain batteries when the boat is unattended. The steering controller connection uses a powered CAN bus for the steering system and should not be connected to the NMEA 2000 network.

Network and control

Once on NMEA 2000, autopilot heading data can be shared with other networked electronics, and control can be handled from a GHC helm control or from a compatible Garmin chartplotter depending on the configuration. Additional NMEA 2000 devices such as a wind sensor can be added to enable sailing functions like wind hold and tack/jibe.

Use on board

This is a good match for skippers running a steer-by-wire-equipped powerboat or sailboat who want an autopilot system that integrates cleanly with a NMEA 2000 backbone and keeps the primary sensor mounted below decks. It fits well on boats that see long coastal runs, offshore passages, or steady trolling where holding a course reduces helm workload for extended periods.