Yamaha FZ 25 2021 Supplementary Service Manual page 191

Fault code No.
Symptoms
Diagnostic code No.
NOTICE
Work when the machine to be repaired is completely cold
Item and components and
Item
probable cause
2 Connection of main harness
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).
3 Harness continuity
4 Installed condition of engine
temperature sensor.
5 Faulty engine temperature sen-
sor.
6 ECU malfunction
7 EG warning light, delete the
fault code.
SELF-DIAGNOSTIC FUNCTION AND
DIAGNOSTIC CODE TABLE
P0197/P0198
Open or short circuit in the engine temperature sensor
P0197 (ground fault) P0198 (open circuit/sky fault)
D11 (Engine temperature sensor)
Defective connections  Re-
connect or replace the harness.
Open or short circuit  Replace
the harness.
Between ECU and engine tem-
perature sensor
In the case of P0198, check the
following:
Between the engine tempera-
ture sensor and the sensor
ground
Check the installation part for
looseness, stuck places.
Check if the mounting position
is OK.
Check in diagnostic mode (code
No. D11).
When engine is cold: Displays
the temperature close to the
ambient temperature.
An indicated value is out of the
specified range.  Replace the
engine temperature sensor.
Replace the ECU.
Delete this fault code with the
status "Recovered" in the
Yamaha diagnostic tool.
6-61
Actions
Turn the main switch to "ON",
and then check the condition of
the fault code in diagnostic mode
of the Yamaha diagnostic tool.
Condition is Recovered  Go to
item 7 and finish the service.
Condition is Detected  Go to
item 3
Turn the main switch to "ON",
and then check the condition of
the fault code in diagnostic mode
of the Yamaha diagnostic tool.
Condition is Recovered  Go to
item 7 and finish the service.
Condition is Detected  Go to
item 4.
Turn the main switch to "ON",
and then check the condition of
the fault code in diagnostic mode
of the Yamaha diagnostic tool.
Condition is Recovered  Go to
item 7 and finish the service.
Condition is Detected  Go to
item 5.
Turn the main switch to "ON",
and then check the condition of
the fault code in diagnostic
mode of the Yamaha diagnostic
tool.
Condition is Recovered  Go to
item 7 and finish the service.
Condition is Detected  Go to
item 6.
Finish the service.
ELEC
Confirmation procedure after
actions
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