Help thread: Yamaha FZ6 fuel pump relay coil gets power only in diagnostic mode

For Yamaha FZ6 fuel pump relay coil gets power only in diagnostic mode, I would not start by clearing codes. Photograph the code, check battery voltage at rest and while cranking, then inspect the connector related to the system. A weak supply can make a scanner sound more dramatic than the bike really is.

Do not underestimate old fuel, low battery voltage, or a loose ground. They love pretending to be expensive components. That is how I would approach Yamaha FZ6 fuel pump relay coil gets power only in diagnostic mode before spending money.

What would be the one tool you would want on the bench before touching Yamaha FZ6 fuel pump relay coil gets power only in diagnostic mode?

Thomas Spagnoli: workshop approach for Yamaha FZ6 fuel pump relay coil gets power only in diagnostic mode

My workshop rule for Yamaha FZ6 fuel pump relay coil gets power only in diagnostic mode is simple: prove the basic condition first, then decide whether the clever part is actually needed.

1. Record the exact code, freeze-frame data if available, and whether Yamaha FZ6 fuel pump relay coil gets power only in diagnostic mode returns immediately or only after riding.
2. Check battery voltage, charging voltage, main grounds, and scanner connection quality before trusting the code as a failed component.
3. Inspect the relevant connector for spread pins, moisture, corrosion, and loom tension near steering head or engine heat.
4. Clear the code only after writing it down, then reproduce the condition and see what comes back first.

If the result changes hot versus cold, or under load versus idle, write that down. Those conditions are not noise; they are clues.

If you are new to this, join the free Motorcycle Mechanics Course on the platform. I made it to explain the workshop logic behind cases like Yamaha FZ6 fuel pump relay coil gets power only in diagnostic mode, not just to list random parts.

Bring one result at a time and the forum can narrow it down properly. That is how a thread becomes a real workshop note.

Small update from my side: I found one suspect connector and I am cleaning it before touching anything more expensive. I will post the exact result, even if the answer ends up being embarrassingly simple.