Yamaha YZF-R1S Service Manual - Elec
8-51
FUEL PUMP SYSTEM
ELEC
YES
NO
5. Starting circuit cut-off relay (fuel injection
system relay)
S Disconnect the starting circuit cut-off relay
coupler from the wire harness.
S Connect the pocket tester (Ω 1) and bat-
tery (12 V) to the starting circuit cut-off relay
coupler as shown.
Replace the starting
circuit cut-off relay.
Positive battery lead
! red/black
Negative battery lead
! blue/yellow
1
2
Positive tester probe
! red
Negative tester probe
! red/blue
3
4
S Does the starting circuit cut-off relay have
continuity between red and red / blue?
YES
NO
6. Fuel pump resistance
S Disconnect the fuel pump coupler from the
wire harness.
S Connect the pocket tester (Ω 1) to the fuel
pump coupler as shown.
Properly connect or
repair the fuel sys-
tem’s wiring.
1
2
Positive tester probe
! red/blue
Negative tester probe
! black
EAS00817
YES
NO
Fuel pump resistance
0.2
X 3.0 Ω at 20_C (68_F)
S Is the fuel pump OK?
Replace the fuel
pump.
S Measure the fuel pump resistance.
7. Wiring
S Check the entire fuel pump system’s wiring.
Refer to “CIRCUIT DIAGRAM”.
S Is the fuel system’s wiring properly con-
nected and without defects?
EAS00818
Replace the ECU.
EAS00759