Yamaha YZF-R1P 2001-2003, Service Manual

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GEN
INFO
FEATURES
Lean angle cut-off switch
The lean angle cut-off switch stops the supply of fuel to the engine in case the motorcycle overturns.
When the motorcycle is in the normal state, the cut-off switch outputs a constant voltage of approxi-
mately 1.0 V (low level). When the motorcycle tilts, the float in the switch tilts in proportion to the tilt
of the motorcycle. However, the voltage output to the ECU remains unchanged at the low level.
When the tilt of the motorcycle exceeds 65 degrees (according to the tilt of the float), the signal from
the sensor increases to approximately 4.0 V (high level). When the ECU receives the high-level volt-
age, it determines that the motorcycle has overturned, and stops the delivery of fuel to the engine by
turning OFF the fuel injection system relay that powers the fuel pump and the injectors. Once the
cut-off switch is tripped, the ECU maintains this state; therefore, even if the motorcycle has recov-
ered its upright position, this state will not be canceled unless the main switch is turned OFF, and
then turned back ON.
È
Output voltage
É
High level
Ê
Low level
Ë
Cut-off switch tilt angle
Ì
Fuel injection system relay OFF