P1602; Troubleshooting - Yamaha MT-09 2021 Service Manual

EAS20615

P1602

EAS33095

TROUBLESHOOTING

Item
Malfunction in ECU internal circuit (malfunction of ECU power cut-off function).
Fail-safe system
• Able/Unable to start engine
• Able/Unable to drive vehicle
Procedure
1. Installed condition of battery leads.
• Check the installed condition of the battery and battery leads (loose bolts).
Is check result OK?
YES
→ Go to step 2.
NO
a. Reinstall or replace the battery leads.
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 7, and complete the service.
NO
→ Go to step 2.
2. Connection of starter relay 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 7, and complete the service.
NO
→ Go to step 3.
3. Connection of 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).
9-231
P1602