Suzuki GSX-R750, Service Manual

Page: 160 / 495

FI SYSTEM AND INTAKE AIR SYSTEM 4-13
TOS
30A
IG SWITCH
15A
10A
FP RELAY
SIDE-STAND RELAY
ENGINE
STOP
SWITCH
To Starter button
SIDE-STAND
SWITCH
FI #1
#2
#3
#4
FUEL
PUMP
ECM
BATTERY
CKPS
FUEL PUMP CONTROL SYSTEM
When the ignition switch is turned on, current from the battery flows to the fuel pump motor through the
side-stand relay and the fuel pump relay causing the motor to turn.
Since the ECM has a timer function, the fuel pump motor stops turning in three seconds after the switch has
been turned on.
Thereafter, when the crankshaft is turned by the starter motor or the engine has been started, the engine
revolving signal is input to the ECM. Then, current flows to the fuel pump motor from the battery through the
side-stand relay and the fuel pump relay so that the pump continues to function.
A tip over sensor is provided in the fuel pump control circuit. By this provision, anytime the motorcycle tips
over, the tip over sensor sends a signal to the ECM to turn off power to the fuel pump relay, causing the fuel
pump motor to stop. At the same time, current to the fuel injectors as well as the ignition coil is interrupted,
which then stops the engine.