The Garmin Reactor™ 40 Steer-by-wire Corepack for Yamaha® Helm Master™ without GHC™ (MPN: 010-00705-91) delivers seamless, full-featured electronic autopilot integration specifically tailored for boats powered by Yamaha’s Helm Master™ outboard control system. Utilizing a solid-state 9-axis Attitude Heading Reference System (AHRS), the Reactor 40 Course Computer Unit (CCU) reacts dynamically to sea conditions to maintain precise heading control, minimize course drift, and optimize fuel efficiency. By connecting directly to Yamaha’s proprietary digital steering network via an included gateway interface, the system eliminates the need for separate hydraulic pumps or mechanical feedback units. Operating without a standalone GHC control display, this corepack communicates across the NMEA 2000® network to allow complete autopilot control, heading adjustments, and Auto Guidance route tracking directly through a networked, compatible Garmin MFD or chartplotter.

Technical Specification

1. Reactor™ 40 Steer-by-Wire CCU (Course Computer Unit)

Feature / Parameter	Specification
Garmin Part Number (MPN)	`010-00705-91`
Physical Dimensions	3 19/32″ diameter (91.4 mm)
Weight	5.6 oz (159 g)
Sensor Type	Solid-state 9-axis AHRS (Attitude Heading Reference System)
Case Material	Fully gasketed, high-impact plastic
Water Rating	IEC 60529 IPX7 (waterproof up to 1m depth for 30 min)
Operating Temperature	-15°C to 55°C (5°F to 131°F)
NMEA 2000 Supply Voltage	9V to 16V DC
NMEA 2000 LEN	3 (150 mA)
CCU Cable Length	9.5 ft (3 m)
Display Requirement	Requires networked Garmin GPSMAP® / ECHOMAP™ MFD (No GHC display included)

2. Yamaha® Autopilot Gateway Unit

Parameter	Specification
Dimensions (L x W x H)	5 1/8″ x 2 3/8″ x 1″ (130 x 60 x 25 mm)
Weight	Less than 1 oz (28 g)
Function	Translates digital CAN-bus commands between Garmin CCU and Yamaha Helm Master™ network
Steering System Compatibility	Legacy Yamaha® Helm Master™ systems (Note: Not compatible with Helm Master EX®)