Mercury MerCruiser 3.0 MPI Installation Manual page 104

STARTING AND ELECTRICAL
• SmartCraft sensor connections
Secure the wiring and position the engine connector out of the way until the engine is installed.
After the engine is in place, make the single connection between the transom and the engine.
TRANSOM GROUND CONNECTION
The ground wire for the transom is incorporated into the transom harness included with the engine.
Connect the ground wire in the transom harness under the bonding strap screw on the transom.
Do not connect any other ground wires here.
Use the ground studs on the flywheel housing for other grounding needs.
NOTE: In some cases, a ground wire to connect to the flywheel housing may be attached to the
bonding screw on the transom. This ground wire is not needed with the transom harness,but can
be connected to the flywheel housing or removed. In any case the grounding wire in the transom
harness must be connected to the bonding strap screw.
Ground wire from the transom harness to the transom bonding strap screw
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c
a
h
g
f
Transom harness—MPI
a - 16‑pin connector to engine harness
b - SmartCraft steering sensor
c - SmartCraft petot sensor
d - MerCathode
a
a - Bonding strap screw
b
25155
d
e
e - Trim gauge sender (orange with white
stripe is for analog gauges)
f - Trim gauge sender ground (black is
common)
g - Trim gauge sender (orange with pink
stripe is for digital gauges)
h - Transom ground (to the transom
bonding screw)
b
25173
b - Ground wire from transom harness
SECTION - 7
90-899883183 DECEMBER 2007