Mercury Mariner 200, 225 Optimax Outboards Service Manual, 90-855348, Page 116Get this manual
Route TAN lead on starboard side of engine to engineremote control harnessConnect as shown LIGHT BULB POSITION B
Use this position when instrument lighting is wired directly to the ignition key switch(Instrument lights are on when ignition key switch is turned on
IMPORTANT: Tape back and isolate any unused wiring harness leads
28086Lead from Temperature SenderEngineRemote Control Harness
Oil Level Gauge Wiring