Bafang error 06: Low voltage protection
Bafang UART systems (BBS01/BBS02/BBSHD, hub drives with C961/500C/850C/DP C18 UART)WarningRide with caution
Battery voltage dropped below the controller's cut-off, so power is cut to protect the cells. Typically the bike shows full bars at rest but collapses to this code under load. It clears once the voltage recovers, then returns as soon as you accelerate.
Likely causes
- Battery genuinely empty or nearly empty
- Aged or unbalanced battery pack sagging heavily under load
- Poor battery contacts, corroded terminals or a loose battery lock
- Undersized battery for a high-current motor (BBSHD on a small pack)
- Cold weather reducing pack capacity
- Wrong low-voltage cut-off set in the controller (after reprogramming or 36V/48V mismatch)
How to fix Bafang error 06
- Charge the battery fully and test again
- Clean the battery contacts and check the battery clicks firmly into its mount
- Reduce the current limit or assist level; if the error stops, the pack cannot deliver the current
- Test the pack: if voltage drops several volts under load and bounces back, cells are weak or unbalanced
- Check the controller's low-voltage cut-off matches your battery (36V vs 48V vs 52V)
- Have the battery tested or rebuilt at a shop if it sags under load
Go to a dealer if: Go to a shop when a fully charged pack still trips the code under load; the battery likely needs cell replacement.
Warranty: Battery packs usually carry 1-2 years of warranty; a pack that sags heavily within that period is a valid claim.
Typical cost: Fixing contacts is free; a battery rebuild or replacement runs EUR/USD 250-700.
Warranty: Battery packs usually carry 1-2 years of warranty; a pack that sags heavily within that period is a valid claim.
Typical cost: Fixing contacts is free; a battery rebuild or replacement runs EUR/USD 250-700.
Still stuck? Take a photo of the display and show it to a local e-bike workshop. Bring the bike's system name (e.g. Bosch Performance Line CX) and the exact code; that saves diagnostic time and money.
Frequently asked
Can I reset error 06?
It clears itself when the voltage recovers, but it will come back under load until the battery issue is solved.
Can I keep riding?
Only gently. Repeated deep sags damage the pack further and can strand you.
Is error 06 covered by warranty?
If the battery is within its warranty and not abused, yes. Bad contacts or a wrong voltage setting are not.
Related Bafang codes
Not an official Bafang document. Compiled from workshop experience and public service information; details can differ per system version and bike brand.