1997+ Mercury 35/40HP 2 Cylinder Outboards Service Manual PN 90-826148R2, Page 85Get this manual
Rectifier Test WARNING Disconnect battery leads from battery before testing rectifier
NOTE: Rectifier can be tested without removing from engine1Disconnect all wires from terminals on rectifier2Use an ohmmeter (R 1000 scale) and perform the following testRefer to drawing for rectifier terminal identification
Terminal Terminal Terminal Stator Terminals Positive Terminal Ground
Rectifier Test (continued)
Connect red meter lead to ground, black lead alternately to terminals "a" and "c"
Continuity Indicated Connect black meter lead to ground, red lead alternately to terminals "a" and "c"