Suzuki GSX-R750 Service Manual page 177

Step
1 1) Turn the ignition switch OFF.
2) Remove the front seat. Refer to "Exterior Parts Removal
and Installation in Section 9D (Page 9D-11)".
3) Check the ECM coupler for loose or poor contacts. If OK,
then measure the ECM input voltage.
4) Disconnect the ECM coupler. Refer to "ECM Removal
and Installation in Section 1C (Page 1C-1)".
5) Insert the needle pointed probe to ECM coupler.
6) Measure the voltage between terminal "10" and ground.
Special tool
(A): 09900–25008 (Multi-circuit tester set)
(B): 09900–25009 (Needle pointed probe set)
Tester knob indication
Voltage ( )
ECM input voltage
Battery voltage
((+) terminal: "10" – (–) terminal: Ground)
ECM couplers (Harness side)
(B)
"10"
Is the voltage OK?
Action
I837H1110143-02
(A)
I837H1110093-01
Engine General Information and Diagnosis:
Yes
• Fuel pump relay
circuit malfunction.
Refer to "DTC "C41"
(P0230-H/L): FP
Relay Circuit
Malfunction
(Page 1A-101)".
• R/Bl wire open or
short or poor "10"
connection.
• Power source of
speedometer shorted
to the grand or open.
• If wire and
connection are OK,
intermittent trouble or
faulty ECM.
• Recheck each
terminal and wire
harness for open
circuit and poor
connection.
• Replace the ECM
with a known good
one, and inspect it
again. Refer to "ECM
Removal and
Installation in Section
1C (Page 1C-1)".
1A-105
No
Open or short circuit in
the R/Bl wire.