2003 Johnson ST 6/8 HP 4 Stroke Outboards Service Manual, PN 5005471, Page 64Get this manual
ELECTRICAL CHARGING SYSTEM
Stator Resistance Tests
IMPORTANT: Disconnect battery cables before
proceeding with this checkDisconnect stator yellow and yellowgray connectorsConnect ohmmeter between the yellow and yellowgray stator leads: Ohmmeter must show 1.38 to 1.68 ohms
Rectifier Resistance Tests
IMPORTANT: Disconnect battery cables before
proceeding with this checkDisconnect all rectifier leads from wiring harnessConnect one ohmmeter lead to clean engine groundConnect the other lead to the rectifier yellowgray lead Note the readingReverse the ohmmeter connections or press the "reverse polarity" button and note the readingPerform the same procedure on the yellow rectifier leadNote the readings high reading in one direction and low reading in the other direction indicates the diode is OK Two high readings or two low readings indicate the diode is damagedDR5882
Repair or replace stator if reading is not correctCheck stator for grounded condition: Disconnect both ohmmeter leadsConnect one ohmmeter lead to clean engine ground and move the other ohmmeter lead alternately to both stator leads: Ohmmeter should show high reading If ohmmeter shows low reading, stator, or its leads, is grounded