Mercury 3.0 MPI ECT Operation & Maintenance Manual page 19

A 15‑amp accessory fuse is located on the rear of the engine. This fuse protects the accessory circuits.
In the ignition switch "I" terminal lead, there may be a 20‑amp fuse that protects the electrical system. Check for an open fuse
or open circuit breaker if you turn the ignition key to the start position and nothing happens.
The power trim system is protected from overload by a 110‑amp fuse and a 20‑amp spade fuse on the power trim pump. The
trim pump may also have an in‑line circuit protection device in the power trim positive lead near the battery switch or battery
connection.
a
90-8M0113856 DECEMBER 2015
eng
Accessory fuse
Ignition switch fuse—typical
b
Section 1 - Getting to Know Your Power Package
7524
mc70525-1
Power trim fuses
a - 20‑amp spade fuse
b - 110‑amp fuse
9208
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