If you have twin Volvo Penta EVC engines there is a quick way to check if you have a “sync” cable already installed and therefore only need a single YDEG-04 Engine Gateway for your boat.
The basic test is to switch the cables of the EVC tachometers. If the port tachometer shows data of the starboard engine, it means that you need a dedicated gateway for each engine (it is less expensive than installing a sync cable). If the port tachometer shows port engine data, then one gateway is enough.

