Mercury Mariner 30/40 4-Stroke Outboard Service Manual 1998, Page 134Get this manual
WIRING DIAGRAMS
Route TAN lead on starboard side of engine to engineremote control harnessConnect as shown
IMPORTANT: Tape back and isolate any unused wiring harness leads
aLead from Temperature SenderEngineRemote Control Harness
Engine Synchronizer Wiring Diagram
LIGHT BULB POSITION Use this position when using separate light switch for instrument lighting