Mercury Mariner Service Manual 6, 8, 9.9 210CC Sailpower, Page 25Get this manual
Rectifier Test AWARNING
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 photo for rectifier terminal identificationabcdefTerminal Terminal Terminal Alternator Terminals Positive Terminal Ground
Connect red meter lead to ground, black lead alternately to terminalsa" andc",
Continuity Indicated Connect black meter lead to groundred lead alternately to terminals "a" andc"No Continuity IndicatedConnect black meter lead to groundred lead alternately to terminalsa" and "c"No Continuity Indicated Connect black meter lead to terminalb", red lead alternately to terminalsa" andc"Continuity Indicated Replace rectifie r