Mercury 225 EFI, Service Manual

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WIRING DIAGRAMS
90-884294 OCTOBER 2001 Page 2D-57
Alarm Messages
These messages will appear and the horn will sound if there is a problem detected in one
of the outboard systems.
NOTE: The warning system will alert the operator to the potential problems listed in the
chart. Refer to explanations following.
PROBLEM TACHOMETER
DISPLAY
SPEEDOMETER
DISPLAY
ENGINE
GUARDIAN
SYSTEM
ACTIVATED
BATTERY *
ENGINE DATA BUS
FAULT – HORN
FAULT – IGNITION
FAULT – INJECTOR
FAULT – OIL PUMP
FAULT – SENSOR *
FAULT – SPEEDO
FAULT – WATER TEMP
LOW FUEL
LOW OIL
OVERHEAT
OVER SPEED
PRESSURE
RESERVE OIL
UNIT MISMATCH
(MULTI ENGINE)
WATER IN FUEL
* Throttle and manifold pressure sensors only
OVERHEAT
a
a - Water Pump Indicator Hole
The overheat alarm message appears and the warning horn begins sounding continuous-
ly. The Engine Guardian System will start limiting engine power.
If the engine overheats, immediately reduce throttle speed to idle. Shift outboard into neu-
tral and check for a steady stream of water coming out of the water pump indicator hole.
NOTE: The throttle will have to be returned to idle to reset the system.
If no water is coming out of the water pump indicator hole or flow is intermittent, stop en-
gine and check cooling water intake holes for obstruction. If no obstruction is found, this
may indicate a blockage in the cooling system or a water pump problem. Operating the
engine while overheated will cause engine damage.
If a steady stream of water is coming out of the water pump indicator hole and the warning
horn continues to sound, there still may be insufficient cooling water or an engine problem.
Stop engine. Operating the engine while overheated will cause engine damage.