C24", "C25", "C26" Or "C27" Ignition System Malfunction; C28" Stv Actuator Circuit Malfunction - Suzuki GSX-R750 Service Manual

"C24", "C25", "C26" or "C27" IGNITION SYSTEM MALFUNCTION

*Refer to the IGNITION SYSTEM for details. (7-20)

"C28" STV ACTUATOR CIRCUIT MALFUNCTION

DETECTED CONDITION
The operation signal does not reach the STV
actuator.
STVA position sensor voltage low or high.
(
0.2 Sensor Voltage
without the above range.
INSPECTION
• Lift and support the fuel tank with its prop stay. (4-51)
1
Turn the ignition switch OFF.
Check the STV actuator lead wire coupler for loose or
poor contacts.
Turn the ignition switch ON.
Check the movement of the STV actuator.
Yes
2-A
Check the installation, the play and the slack of ST valve
control cables. (4-73)
If it is necessary, adjust the ST valve control cables.
(4-72)
If C28 code is indicated after adjusting the cable, perform
the section 3-A .
3-A
Turn the ignition switch OFF.
Disconnect the STVA position sensor lead wire coupler 1.
Turn the ignition switch ON.
Measure the voltage between the Red wire terminal and
B/Br wire terminal.
Position sensor input voltage: 4.5 – 5.5 V
[ 09900-25008: Multi circuit tester
V Tester knob indication: Voltage (
Yes
To 4-A (Next page)
)
4.8 V
No
To 2-B (4-47)
( + + + + + Red – - - - - - Ground
+ + + + + Red – - - - - - B/Br
)
No
Loose or poor contacts on
the ECM coupler.
Open or short circuit in the
Red wire or B/Br wire.
FI SYSTEM AND INTAKE AIR SYSTEM 4-45
POSSIBLE CAUSE
• STV actuator maladjusted.
• STV actuator circuit open or short.
• STVA motor malfunction.
• STVA position sensor malfunction.
1
2-A
3-A
)
3-A
V
Ground
0 – 1.0 mm 0 – 1.0 mm
B/Br
Red