Dtc "C40" (P0505, P0506 Or P0507): Isc Valve Circuit Malfunction - Suzuki GSF650A Service Manual

1A-93 Engine General Information and Diagnosis:

DTC "C40" (P0505, P0506 or P0507): ISC Valve Circuit Malfunction

Detected Condition and Possible Cause
Detected Condition
C40 The circuit voltage of motor drive is
(P0505) unusual.
C40 Idle speed is lower than the desired idle
(P0506) speed.
Idle speed is high than the desired idle
speed.
C40
(P0507)
Wiring Diagram
Troubleshooting
CAUTION
!
• Be careful not to disconnect the ISC valve coupler at least 5 seconds after ignition switch is turned
to OFF.
If the ECM coupler is disconnected within 5 seconds after ignition switch is turned to OFF, there is a
possibility of an usual valve being written in ECM and causing an error of ISC valve operation.
• When using the multi-circuit tester, do not strongly touch the terminal of the ECM coupler with a
needle pointed tester probe to prevent the terminal damage or terminal bend.
NOTE
After repairing the trouble, clear the DTC using SDS tool. Refer to "Use of SDS Diagnosis Reset
Procedures (Page 1A-15)".
ISC valve
W/Y
Lbl
Lg
Dbr
ECM coupler (Harness side)
Possible Cause
• ISC valve circuit open or shorted to the ground.
• Air passage clogged.
• ISC valve is fixed.
• ISC valve Preset position is incorrect.
• Disconnect ISC valve hose.
• ISC valve is fixed.
• ISC valve Preset position is incorrect.
W/Y
Lbl
Lg
Dbr
B817H21104022
ECM
49 IS1B
36
IS1A
48 IS2B
35 IS2A
I718H1110105-03
I718H1110240-01