10-Pin vs 14-Pin Harness Guide
How to Identify a Mercury 10-Pin vs 14-Pin Harness
How do you know if your mechanical shift Smartcraft engine is a 14 pin or 10 pin?
Many Mercury SmartCraft mechanical-shift engines use either a 10-pin or 14-pin helm harness connection. Knowing which version your engine uses is important when selecting gauges, SmartCraft accessories, or replacement harnesses.
In 2006 Mercury switched all Smartcraft non-DTS (mechanical shift) engines over to a 14-pin style key switch harness. This new 14 pin harness incorporates all the wires from the 10 pin blue cable which eliminates the need for routing a separate blue cable. You can still use the 10-pin blue cable architecture on a 14-pin engine, but it's not typical.
Below are the serial number breaks so you can easily identify if your engine has the 14-pin connection:
Mercury Outboards - Serial #1B228965 and up
Mercruiser Engines - Serial #0W600000 and up