Yamaha MTN850-A 2017 Service Manual page 415

Fault code No. P0201
Fault code No.
Item
Fail-safe system
Diagnostic code No.
Actuation
Procedure
Probable cause of malfunc-
Item
tion and check
1 Connection of fuel injector #1
coupler.
Check the locking condition of
the coupler.
Disconnect the coupler and
check the pins (bent or broken
terminals and locking condition
of the pins).
2 Defective fuel injector #1.
3 Connection of ECU coupler.
Check the locking condition of
the coupler.
Disconnect the coupler and
check the pins (bent or broken
terminals and locking condition
of the pins).
4 Wire harness continuity.
5 Malfunction in ECU.
6 Delete the fault code and check
that the engine trouble warning
light goes off.
P0201
Fuel injector #1: malfunction in fuel injector #1.
Able to start engine (depending on the number of faulty cylinders)
Able to drive vehicle (depending on the number of faulty cylinders)
36
Actuates fuel injector #1 five times at one-second intervals.
The "check" indicator on the Yamaha diagnostic tool screen comes on
each time the fuel injector is actuated.
Disconnect the fuel pump coupler. Check that fuel injector #1 is actuated
five times by listening for the operating sound.
Maintenance job
Improperly connected  Con-
nect the coupler securely or
replace the wire harness.
Measure the fuel injector resis-
tance.
Replace if out of specification.
Refer to "CHECKING THE
FUEL INJECTORS" on page
8-174.
Improperly connected  Con-
nect the coupler securely or
replace the wire harness.
Open or short circuit  Replace
the wire harness.
Between fuel injector coupler
and ECU coupler.
red/black–red/black
Between fuel injector coupler
and relay unit coupler.
red/blue–red/blue
Replace the ECU.
Refer to "REPLACING THE
ECU (Engine Control Unit)" on
page 8-157.
Start the engine and let it idle for
approximately 5 seconds.
Confirm that the fault code has
a condition of "Recovered"
using the malfunction mode of
the Yamaha diagnostic tool, and
then delete the fault code.
8-58
FUEL INJECTION SYSTEM
Confirmation of service com-
Execute the diagnostic mode.
(Code No. 36)
Operating sound  Go to item
6.
No operating sound  Go to
item 2.
Execute the diagnostic mode.
(Code No. 36)
Operating sound  Go to item
6.
No operating sound  Go to
item 3.
Execute the diagnostic mode.
(Code No. 36)
Operating sound  Go to item
6.
No operating sound  Go to
item 4.
Execute the diagnostic mode.
(Code No. 36)
Operating sound  Go to item
6.
No operating sound  Go to
item 5.
pletion