Mercury 35/40HP 2 Cylinder Outboards Service Manual PN 90-42794--1, Page 263Get this manual
Troubleshooting the "Down" and "Up" Circuits (All Circuits Inoperative) Remote Control Not Equipped with Trailer Button
Check in- line fuse (under cowl) to see if fuse is blown
Blown Fuse:
Fuse Not Blown:
Correct problem that caused fuse to blow Replace fuse
Connect Voltmeter red lead to Point and black lead to ground Battery voltage should be indicated
No Voltage Indicated:
Battery Voltage Indicated:
Check battery leads for poorconnections or open circuits Check battery charge
Connect Voltmeter red lead to Point and black lead to ground Depress "Up" trim button and check for battery voltageBattery Voltage Indicated: