
TROUBLESHOOTING
Trouble Codes
13-10
BY Service Manual
© 2009 Yanmar Marine International
TROUBLE CODES
Working Procedure
Try to form a comprehensive view of the problem. Start by asking the operator the following:
• Symptoms
• Conditions in which the fault occurs
• How often the fault occurs
• If the trouble codes have been erased
Then, extract all the stored trouble codes.
Compare them and try to conclude the probable cause of the fault before taking any other measures. The
trouble codes are stored in the order they were registered.
Diagnostic Trouble Codes
Some conditions will produce an alarm but do not generate a trouble code. An example is engine overheat
(over 108°C [226°F]) 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.
Conditions that set a trouble code are generally caused by a sensor or other component sending an
out-of-normal range signal to the ECU. An example is a disconnected intake air pressure sensor which
would set a P0237 code.
Code
Part or System
Mode
Run Or
Conditi
on
Engine
Can Start
Check
Engine
Alarm
No
Code
Coolant Temp
Under 0°C (32°F)
1000 rpm
yes
no
No
Code
Coolant Temp
Over 108°C (226°F)
reduce
yes
no
No
Code
Coolant Temp
Over 110°C (230°F)
reduce
yes
alarm
No
Code
Charge Air Temp
Over 110°C (230°F)
reduce
yes
no
No
Code
Boost Pressure Reading
4BY2 - over 1.9 bar (27.5 psi) (relative
*
) or 2.9 bar
(42.0 psi) (absolute
**
)
6BY2 - over 2.3 bar (33.3 psi) (relative*) or 3.3 bar
(42.9 psi) (absolute)
reduce
yes
alarm
No
Code
Fuel Temperature
Over 90°C (194°F)
reduce
yes
no
No
Code
Neutral Switch
Only in case of analog throttle or in case of
CAN-fault (U0001), wrong configuration - neutral
position
no
no
alarm
P0001
Fuel Metering Unit
Not connected
reduce
yes
alarm
P0003
Fuel Metering Unit
Short circuit to Ground
no
no
alarm
P0004
Fuel Metering Unit
Short circuit to B+
reduce
yes
alarm
P0087
Rail Pressure Governor
Deviation
Fuel rail pressure out of range
reduce or
shut off
depends
on fault
alarm