Yamaha YZF-R1 Series Service Manual page 686

EAS20599
P0638
EAS33079
TROUBLESHOOTING
Item
YCC-T drive system: malfunction detected.
Fail-safe system
• Able/Unable to start engine
• Able/Unable to drive vehicle
Procedure
1. Connection of throttle servo motor 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 "ON", and then check the condition of the DTC using the malfunction mode
of the YDT.
Is it in the "Recovered" condition?
YES
→ Go to step 8, and complete the service.
NO
→ Go to step 2.
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).
Is the coupler condition normal?
YES
→ Go to step 3.
NO
a. Connect the coupler securely or replace the wire harness.
b. Turn the main switch to "ON", and then check the condition of the DTC using the malfunction mode
of the YDT.
Is it in the "Recovered" condition?
YES
→ Go to step 8, and complete the service.
NO
→ Go to step 3.
3. Check the electronic throttle valve fuse.
Is check result OK?
YES
→ Go to step 4.
9-189
P0638