1998+ Mercury Mariner 25HP Bigfoot Service Manual, Page 89Get this manual

IGNITION
SPARK PLUG CAP RESISTOR TEST

METER TEST LEADS RED BLACK

METER SCALE RX1K

READING (W) 3.5 5.2 35-52

• ATV
• Jet Ski
• Outboard Motors
• Personal Watercraft
• Snowmobiles
• Stern Drives