Trouble Codes; Working Procedure; Diagnostic Trouble Codes - Yanmar BY Series Service Manual

TROUBLESHOOTING

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
No
Coolant Temp
Code
No
Coolant Temp
Code
No
Coolant Temp
Code
No
Charge Air Temp
Code
No
Boost Pressure Reading
Code
No
Fuel Temperature
Code
No
Neutral Switch
Code
P0001 Fuel Metering Unit
P0003 Fuel Metering Unit
P0004 Fuel Metering Unit
Rail Pressure Governor
P0087
Deviation
13-10
Mode
Under 0°C (32°F)
Over 108°C (226°F)
Over 110°C (230°F)
Over 110°C (230°F)
4BY2 - over 1.9 bar (27.5 psi) (relative
(42.0 psi) (absolute
6BY2 - over 2.3 bar (33.3 psi) (relative*) or 3.3 bar
(42.9 psi) (absolute)
Over 90°C (194°F)
Only in case of analog throttle or in case of
CAN-fault (U0001), wrong configuration - neutral
position
Not connected
Short circuit to Ground
Short circuit to B+
Fuel rail pressure out of range
© 2009 Yanmar Marine International
Run Or
Conditi
on
1000 rpm
reduce
reduce
reduce
*
) or 2.9 bar
**
)
reduce
reduce
no
reduce
no
reduce
reduce or
shut off
BY Service Manual

Trouble Codes

Check
Engine
Engine
Can Start
Alarm
yes no
yes no
yes alarm
yes no
yes alarm
yes no
no alarm
yes alarm
no alarm
yes alarm
depends
alarm
on fault