SHIMANO STEPS error and warning codes · SHIMANO STEPS

W031 Error on SHIMANO STEPS

What it means + how to fix it From the brand

Quick answer

W031 on the SHIMANO STEPS (EP8, EP6, E8000, E7000, E6100, E5000 and others) means “The chain tension may not yet be adjusted or the crank may not be installed in the proper position..” Most likely cause: a fault in an electronic shifting system (only on bikes that have one). Try this first: turn it off and on again.

Try this first

Free, and each takes under 5 minutes.

Turn it off and on again

Code meanings vary by brand. The same number can mean different things on different displays and controllers. Check your bike's manual to confirm.

About the SHIMANO STEPS (EP8, EP6, E8000, E7000, E6100, E5000 and others)

From Shimano's official Error & Warning Code page on si.shimano.com, checked October 23, 2026. It is one list for all SHIMANO STEPS systems, not split by model. source
Shimano's EP801 / EP600 manual and its special battery and parts manual send riders to this page for error codes. source
The SC-E6100 cycle computer manual also points to this list. An "E" code shown on the entire screen means the product may have malfunctioned. A "W" code means it may have a temporary problem. source
Shimano also lists 5-digit codes (like E01010 or W10000), but says they are only used in E-TUBE PROJECT Professional, the dealer software. They don't show on the bike, so they are not listed here. source
Codes can differ between E-TUBE PROJECT Professional and your cycle computer or app. Older displays may show only some of these codes. source

In plain English

These codes only apply to bikes with electronic gear shifting linked to the motor system. Restart first. If the code stays, the manual's answer is your retailer.

Step-by-step checklist

Work from the top. Steps go from free and easy to shop jobs. Switch the bike off before touching any connector. Tick each step as you go. Your progress is saved on this device.

1Turn it off and on againFree Switch the display off, wait 30 seconds, then switch it back on. If the code clears, note what you were doing when it appeared, in case it comes back.
2Ask a Bafang dealer to read the faultShop job Bafang dealers have a diagnostic tool that reads detailed fault data and can update firmware. It often pins down internal faults quickly.

Parts you might need

As an Amazon Associate I earn from qualifying purchases. These links go straight to Amazon.

Only buy a part if the free steps didn't fix it. Always match the voltage and connector type to your bike.

Electrical contact cleaner spray
Cleans dirt and corrosion from connector pins and battery contacts.
View on Amazon

Still not fixed?

Pages to try next:

When it's time for a shop: if you've worked through every step and the problem is still there, take the bike to an e-bike shop. Bring your notes on when it happens, plus the code.