Mercury Mariner 30/40 4-Stroke Outboard Service Manual 1998, Page 307Get this manual
POWER TRIM
Troubleshooting the Power Trim Electrical System
Refer to wiring diagram on preceding page for location of wire connectionsProblem Trim Switch is inoperative, but the Cowl Switch does operatePossible Cause 1Open wire between Wire Connection (1) and Trim Switch2Faulty Trim SwitchRemedy 1Check for an open connection or cut wire2Replace1Check for an open connection or cut wire2Replace1Check for an open connection 2Check for an open connection 3Check for an open connection4Replace1 Check for an open connection or cut wire2Replace1 Check for open connection or cut wire2Replace 1Check for an open connection2Check for an open connection 3Check for an open connection 4Replace1Replace fusel ocate the cause of the blown fuseCheck electrical wiring for shorted circuit2Replace3Check for open connection or cuI wire4Check for loose or corroded cannection1Check wire connections (4) for loose or corroded condition 2If voltage is present at connections (4) when the appropriate trim button is pressed, then motor is faultyReplace motor1Replace