Raymarine Engine Data Lost — NMEA 2000 Connection Fix

What it means

Raymarine 'Engine Data Lost' (or 'No engine data' / engine gauges greying out) means the plotter is no longer receiving the engine feed from the NMEA 2000 / SeaTalkng backbone.
The engine itself is fine — what's broken is the data path: usually the engine interface gateway, a loose backbone connector, or the engine's data bus being asleep because the ignition is off.

Affected Models

Raymarine Axiom / Axiom Pro / Axiom XL with engine pages enabled
Raymarine eS / gS Series
Systems using an ECI-100 engine interface or a maker's NMEA 2000 gateway (Yamaha, Mercury SmartCraft, Volvo EVC)

Common Causes

Engine ignition off — most engine buses stop broadcasting once the key is out
Engine interface gateway (ECI-100, SmartCraft gateway) lost power or dropped off the backbone
Loose or corroded SeaTalkng / NMEA 2000 backbone connector
Backbone power not switched on (the network needs its own 12V feed, separate from the plotter)
Backbone terminator missing or a T-piece pulled apart
Engine ECU fault that has stopped its data broadcast (rare — usually shows engine warning lights too)

How to Fix It

Check the ignition is on.

Most outboard and sterndrive data buses only broadcast with the ignition live.
If you're sitting at the dock with the key out, 'Engine Data Lost' is expected — turn the key to the run position (engine doesn't need to be running) and the data should reappear within seconds.
Check the backbone power.

A SeaTalkng / NMEA 2000 network needs its own 12V supply at the power T-piece — it isn't powered by the plotter.
If that feed has lost power, everything on the backbone goes quiet, not just engine data.
Confirm the network power LED (where fitted) or measure 12V at the power tap.
Reseat the gateway connector.

Find the engine interface (ECI-100 or the engine maker's gateway) and reseat both its backbone spur and its connection to the engine harness.
Look for corrosion — engine bays are damp.
A status LED on the gateway confirms it has power and is talking.
Check the backbone is intact.

Walk the SeaTalkng backbone looking for a T-piece that's worked loose or a terminator that's fallen off one end.
A backbone missing a terminator becomes unreliable and devices drop in and out.
Both ends of the backbone need a terminator — no exceptions.

Frequently Asked Questions

Should I worry about the engine if this alarm shows?

Not on its own.
'Engine Data Lost' is a communication alarm, not an engine fault — it tells you the plotter can't see the data, not that the engine has a problem.
Watch your physical engine gauges and warning lamps; if those are normal, the engine is fine and you just have a network fault to chase when convenient.