Yamaha YZF-R25 Service Manual page 395

Fault code No.
Item
Actuation
Procedure
Probable cause of malfunc-
Item
tion and check
1 Connection of cylinder-#2 igni-
tion coil coupler.
Check the locking condition of
the coupler.
Disconnect the coupler and
check the pins (bent or broken
terminals and locking condition
of the pins).
2 Connection of ECU coupler.
Check the locking condition of
the coupler.
Disconnect the coupler and
check the pins (bent or broken
terminals and locking condition
of the pins).
3 Wire harness continuity.
4 Installed condition of cylinder-#2
ignition coil.
Check for looseness or pinch-
ing.
5 Defective cylinder-#2 ignition
coil.
6 Malfunction in ECU.
34
Cylinder-#2 ignition coil: open or short circuit detected in the prima-
ry lead of the cylinder-#2 ignition coil.
Actuates the cylinder-#2 ignition coil five times at one-second intervals.
The "CHECK" indicator and "
comes on each time the ignition coil is actuated.
Check that a spark is generated five times.
• Connect an ignition checker.
Maintenance job
Improperly connected → Con-
nect the coupler securely or re-
place the wire harness.
Improperly connected → Con-
nect the coupler securely or re-
place the wire harness.
Open or short circuit → Replace
the wire harness.
Between cylinder-#2 ignition coil
connector and ECU coupler.
gray/red–gray/red
Improperly installed ignition coil
→ Reinstall or replace the igni-
tion coil.
Measure the primary coil resis-
tance of the cylinder-#2 ignition
coil.
Replace if out of specification.
Refer to "CHECKING THE IG-
NITION COILS" on page 8-88.
Execute the diagnostic mode.
(Code No. 31)
No spark → Replace the ECU.
Refer to "REPLACING THE
ECU (engine control unit)" on
page 8-81.
8-50
FUEL INJECTION SYSTEM
" on the Yamaha diagnostic tool screen
Confirmation of service com-
Start the engine and let it idle for
approximately 5 seconds.
Fault code number is not dis-
played → Service is finished.
Fault code number is displayed
→ Go to item 2.
Start the engine and let it idle for
approximately 5 seconds.
Fault code number is not dis-
played → Service is finished.
Fault code number is displayed
→ Go to item 3.
Start the engine and let it idle for
approximately 5 seconds.
Fault code number is not dis-
played → Service is finished.
Fault code number is displayed
→ Go to item 4.
Start the engine and let it idle for
approximately 5 seconds.
Fault code number is not dis-
played → Service is finished.
Fault code number is displayed
→ Go to item 5.
Start the engine and let it idle for
approximately 5 seconds.
Fault code number is not dis-
played → Service is finished.
Fault code number is displayed
→ Go to item 6.
pletion