Malfunction Indicator Lamp - Mercury MerCruiser D2.8L D-Tronic Service Manual

SERVICE MANUAL NUMBER 22

Malfunction Indicator Lamp

The Engine System Monitor Panel provided in the factory instrumentation package is
equipped with a Malfunction Indicator Lamp (MIL). The MIL is a lamp with a check mark (n)
on the colored lens.
•
It informs the operator and service technician that a problem has occurred and that
the vessel is in need of service as soon as reasonably possible.
•
It displays Codes stored by the ECM which help the technician diagnose system
problems.
As a bulb and system check, the lamp will come ON with the key on and the engine not
operating. When the engine is started, the light will turn OFF. If the lamp remains ON, the
self-diagnostic system has detected a problem. If the problem goes away, the light will go
out in most cases after ten seconds, but a code will remain stored in the ECM.
When the lamp remains ON while the engine is operating, or when a malfunction is
suspected due to a driveability problem, an EDI Diagnostic Circuit Check must be
performed. These checks will expose malfunctions which may not be detected if other
diagnostics are performed prematurely.
The ECM has been programmed to illuminate the MIL during or due to the errors associated
with the following devices:
•
Engine Coolant Temperature (ECT) sensor
•
Intake Air Temperature (IAT) sensor
•
Manifold Absolute Pressure (MAP) sensor
•
Throttle Position (TP) sensor and Low Idle Switch (LGS) sensor
•
Instrumented Injector (NBF)
•
Timing Advance Actuator
•
Timing Solenoid Valve
•
Fuel Shut Off Valve
•
Battery + (12 Volts)
•
Fuel Quantity Actuator
•
Fuel Quantity Sensor
•
RPM Sensor
•
EEPROM in ECM
90-860074--1 FEBRUARY 2002
EDI DIAGNOSIS
Page 5E-9