DIAGNOSTIC TROUBLE
CODES
When certain faults occur, or when certain
limits have been exceeded, the engine ECU
may generate a “Check Engine” warning or
turn on a check engine light (if equipped).
Some of these faults may also generate a
DTC or Diagnostic Trouble Code and an
audible alarm. If a DTC is generated, the
engine ECU will store that code or codes for
reference. To read the DTC codes, a special
tool is used by the technician. The
technician then can use a list to more quickly
find the cause of the fault and correct it.
Some conditions will produce an alarm but
do not generate a trouble code. An example
is engine overheat (over 108°C) caused by
an obstructed seawater inlet. The overheat
alarm will sound and the engine torque will
be reduced to protect the engine, but no
code will be set.
Under some conditions, the warning alarm
will sound until the fault code is checked and
corrected. Under other conditions, the alarm
will be canceled if the engine is turned off
and then restarted.
For further information, please contact your
authorized Yanmar distributor or dealer.
TROUBLESHOOTING
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BY Series Operation Manual
© 2008 Yanmar Marine International