How to Reset Shimano Di2 Crash Mode

Founder, Mr. Mamil

After a crash, you might find that your Shimano Di2 rear derailleur has stopped working, leaving you in a difficult situation. This frustrating situation can make you feel helpless, especially if you’re unfamiliar with the Shimano Di2 crash mode or RD protection function.

In this article, I’ll provide a step-by-step guide on resetting your Shimano Di2 system, so you can easily continue your ride.

What is Di2 Crash Mode?

It’s a mechanism to protect the rear derailleur in case of a crash or strong impact. Once activated, the rear derailleur will stop working temporarily.

How do I know if Di2 Crash Mode is on?

The rear derailleur stops working immediately after a crash or if you’ve hit a pothole or uneven road hard.

How to reset the Di2 Crash Mode

Before resetting the Crash Mode, visually inspect the rear derailleur and hanger to ensure they’re not damaged.

10 and 11-speed Shimano Di2

These apply to 10-speed (R7970 / R6770) 11-speed (R9150 / R9000 / R8000 / R6870) and 10-speed Shimano Di2 rear derailleurs.

Follow these steps to reset the crash mode,

  1. Lift the rear wheel.
  2. Press and hold the button on Junction A for five seconds until you see a blinking red light.
  3. Turn the pedals slowly, and the rear derailleur will automatically shift through all the gears to reconnect the motor.
  4. Continue turning the pedals until the shifting completes.

12-speed Shimano Di2

These apply to 12-speed R9200 / R8100) Shimano Di2 rear derailleurs.

The 12-speed rear derailleur has a different design from its predecessors and doesn’t require pressing the reset button.

According to Shimano,

While turning the front chainwheel, operate the shift switch until the gear is shifted from the largest sprocket to the smallest sprocket.

In other words, continue pedaling while shifting to the largest cog, then to the smallest cog. This will turn off the Crash Mode, and the rear derailleur should function normally again.

Alex Lee at Mr.Mamil

Alex Lee is the founder and editor-at-large of Mr. Mamil. Coming from a professional engineering background, he breaks down technical cycling nuances into an easy-to-understand and digestible format here.

He has been riding road bikes actively for the past 12 years and started racing competitively in the senior category during the summer recently.