1999 "EE" Evinrude 200, 225 V6 FFI Outboards Service Manual, P/N 787025, Page 137Get this manual
Perform the following tests if the tachometer does not operateINotel The tachometer circuit is driven by the ECUVerify that all engine and boat wiring and connectors are in good condition
Important
1Check voltage at the batteryUse this reading as your reference for battery voltage2Check for battery voltage between the tachometer purple lead the engine NOT running and the key switch ON
black lead at the dash with
If the voltmeter shows battery voltage, go to Step If the voltmeter shows less than battery voltage, check the purple, purplered, and black circuits, Position fuse, key switch, and the battery connections3Disconnect instrument harness gray lead and black lead at tachometerSet Fluke 29 Series II meter, or equivalent, to Hz scaleConnect meter between gray lead and black lead With engine running at 1000 RPM, meter should indicate 90-105 Hz If reading 90-105 Hz, replace tachometer If other than listed above, check gray lead output at ECU- Reading OKcheck condition of gray circuit- Reading not OKreplace ECU