Yamaha MT-09 2021, Service Manual

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P0 3 00, P0 3 01, P0 3 02, P0 3 0 3
EAS20773
P0 3 00, P0 3 01, P0 3 02, P0 3 0 3
• [P0300] Misfire in multiple cylinders
• [P0301] Misfire in cylinder #1
• [P0302] Misfire in cylinder #2
• [P0303] Misfire in cylinder #3
EAS33318
OUTLINE
Explanation of detection method
The ECU monitors the consistency of the crankshaft rotation by crankshaft position sensor, and if the
angular velocity fluctuates irregularly, the ECU determines that there is a misfire. Two kinds of misfire
judgment are performed according to the number of misfire occurrences and the threshold value.
* Catalyst damage
• The number of misfires per 200 revolutions of the crankshaft exceeds the threshold value, and it is de-
tected that the exhaust gas damages the catalyst, the DTC is stored in the ECU and the MIL starts
flashing.
* Exhaust gas deterioration
• The number of misfires per 1000 revolutions of the crankshaft exceeds the threshold value, and it is
detected that the exhaust gas does not damage the catalyst but affect the exhaust gas emission level,
the DTC is stored in the ECU and the MIL comes on.
Requirement for detection
Related sensors for detection
Intake air pressure sensor, coolant temperature sensor (or engine temperature sensor), front wheel
sensor, rear wheel sensor, crankshaft position sensor, and throttle position sensor
Frequency of detection Always
Time required for detection Always
Malfunction determination
method
• Catalyst damage
When an abnormality is detected three times in one driving cycle, it
is determined to be a pending abnormality and the MIL starts flash-
ing. If this cycle occurs in three consecutive driving cycles, the mal-
function is determined and the MIL comes on.
• Exhaust gas deterioration
If an abnormality is detected four times within one driving cycle, it is
determined to be a pending abnormality. The MIL does not flash at
this time. If this cycle occurs in three consecutive driving cycles, the
malfunction is determined and the MIL comes on.
Driving condition No excessive acceleration or deceleration
Type of detection result Complete, Incomplete
Duration Refer to the conversion table of steady driving time.
Engine starting time No condition specified
O
2
feedback No condition specified
Vehicle speed No condition specified
Gear position No condition specified
Engine speed 2300–6500 r/min