Yamaha MT-09 2021 Service Manual page 627

Is resistance ∞ Ω?
YES
→Go to step 5.
NO
a. Replace the wire harness.
b. Turn the main switch to "ON".
c. Operate the front brake lever, 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 11, and complete the service.
NO
→Go to step 5.
5. Defective front brake light switch.
• Replace the front brake light switch.
Refer to "FRONT BRAKE" on page 4-25.
• Turn the main switch to "ON".
• Operate the front brake lever, 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 11, and complete the service.
NO
→Go to step 10.
6. Connection of wire harness ECU coupler, rear brake light switch coupler, brake light relay coupler
and main switch 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 7.
NO
a. Connect the coupler securely or replace the wire harness.
b. Turn the main switch to "ON".
c. Operate the rear brake pedal, 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 11, and complete the service.
NO
→Go to step 7.
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P056C