Yamaha YZF-R1 Series Service Manual page 743

EAS20644
U0100
EAS33124
TROUBLESHOOTING
Item
Abnormal CAN communication (between ECU and SCU)
Fail-safe system
• Able to start engine
• Able to drive vehicle
Procedure
1. 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).
Is the coupler condition normal?
YES
→ Go to step 2.
NO
a. Connect the coupler securely or replace the wire harness.
b. Turn the main switch to "OFF" and back to "ON", and then check the condition of the DTC using the
malfunction mode of the YDT.
Is it in the "Recovered" condition?
YES
→ Service is completed.
NO
→ Go to step 2.
2. Wire harness continuity.
• Disconnect the SCU coupler "1", joint coupler "2" and ECU coupler "3".
• Open circuit check
Between SCU coupler and joint coupler
Between the joint coupler and ECU coupler
blue/white–blue/white
blue/black–blue/black
blue/white–blue/white
blue/black–blue/black
9-246
U0100