Mercury Mariner 30/40 4-Stroke Outboard Service Manual 1998, Page 72Get this manual
IGNITION
'Recommended Test
(1) (2) (3) (4) DVA TEST (Direct Voltage Adapter) OHM TEST (Resistance Testing) Replace Component and Retest Mechanical TesVRepair
PROBLEMCONDITION No Spark Condition (All Cylinders)
Probable Cause Crank Position Sensor Stator (ECM) Stop Circuit Short to Ground:stop circuit leadlanyard stop switchIiller handle slop bullon (if supplied)remote control harness Ignition Coilprimary Circuit Shorted to Ground Spark Plugs Open Ground Condition: ignition coil stator ground(ECM) High Tension Lead Spark Plug Cap (Resislor) Spark Plug Ground Connection at:Ignition Coil Primary LeadsSIalor(ECM) Primary Coil Supply Leads High Resistance To Ground at:stoplanyard switch (watercorrosion) Weak Charge Coil Ignillon CoilHigh Tension Lead(s) Spark Plug(s) Spark Plug Cap (Resislor) Spark Plug Cap Leak (ECM) Failure