Mercury – Trim Sensor Kit | Digital Trim Angle Feedback | 863187A2

Overview

Most boaters go years without thinking about their trim sensor. It just sits there doing its job—quiet, steady, and taken for granted. But when the readings stop lining up, you feel it right away. The bow does one thing, the gauge shows another, and the whole ride loses a bit of its rhythm. The Mercury Trim Sensor Kit (863187A2) brings that rhythm back. It gives you clean, honest trim information that feels right the moment you bump the switch.

If your engine runs SmartCraft and the 555 control module, this is the piece that keeps the system talking the way it should. Nothing dramatic. Nothing flashy. Just a dependable sensor that puts trust back into the numbers on your display.

Key Features

• Digital trim sensor kit built for SmartCraft-based setups
• Sends smooth, steady trim angle readings to your digital display
• Durable marine construction built for long seasons on the water
• Designed to work with engines using the 555 ECM
• Stays accurate under heat, vibration, and daily use
• Direct-fit installation with a familiar, simple hookup

Engine & Boat Compatibility

• MerCruiser engines with 555 ECM
• Mercury Racing engines with 555 ECM
• Cummins MerCruiser Diesel engines

Performance & Practical Benefits

A trim sensor is a small part, but you feel its influence every time you touch the controls. When this kit is in place, the gauge moves naturally with the engine. No jumping, no lag, no guesswork. You get a reading that matches what the boat is actually doing. That makes trimming up for clean water feel instinctive again, and it helps when you drop the bow into a chop to smooth things out. Even little moments—idling into a slip or lining up for a tight turn—feel more under control.

The sensor is built for the kind of punishment boats see every day. Heat, humidity, long hours at the dock or underway—it holds its calibration through all of it. You install it once, and it settles into the background the way a good sensor should. No drama, just dependable feedback.

Why Buy OEM

With digital systems, the small details matter. Mercury designs this kit specifically for SmartCraft and the 555 module, so the readings stay accurate and the communication stays clean. An aftermarket sensor might look close, but the performance usually tells a different story once it’s actually on the water.

Using an OEM kit means fewer surprises, fewer re-installs, and a sensor that lasts longer. It’s a one-and-done kind of part, and going with the Mercury version keeps the whole system running the way it was built to.

FAQ

Q1: Which engines use the 863187A2 Trim Sensor Kit?
Any SmartCraft engine running the 555 ECM, along with Cummins MerCruiser Diesel models.

Q2: Why choose the OEM version?
It holds calibration better, communicates reliably with SmartCraft, and stands up to real marine use.

Q3: How do I know this is the right kit?
If your engine uses SmartCraft with the 555 module, this is the correct trim sensor kit.

Q4: Can it handle saltwater use?
Yes. It’s sealed and built for long-term service in saltwater or freshwater.

Q5: Is installation fairly simple?
Usually, yes. The connection is direct-fit, though access depends on the boat.