Bafang E-Bike Error Code 04: Meaning + Fix Checklist

TL;DR

Error 04 = The throttle has fault.
Official guidance (Bafang): Check throttle connector/cable; reconnect; replace throttle if needed.

Note: Bafang error codes can vary by display/system (UART vs CAN, model families). This page follows Bafang’s official DP C271 display manual wording.


Quick fix (safe DIY first)

  1. Reseat the throttle connector (power off first).
  2. Inspect the cable for cuts/pinches near the handlebar/head tube.
  3. If unplugging the throttle doesn’t change the behavior, the issue may be elsewhere—shop can test.

60-second checks (what causes repeat codes)

  • Power off → on again, then re-check.
  • Inspect visible connectors (display/controller/battery area) for loose, wet, corroded, bent pins, or damaged cables.
  • If the code appears after rain or washing: dry the bike and avoid pressure washing around the motor/battery mount.

Common causes

  • Throttle connector loose or wet.
  • Damaged throttle cable.
  • Throttle internal failure.

When to stop DIY (go to a shop)

Go to a qualified e-bike shop if:
– The code returns immediately after a restart.
– Assistance cuts in/out while riding (safety issue).
– You see damaged wiring, corrosion, or water intrusion.
– The official fix references dealer tools (e.g., BESST) or component replacement.


Related guides


Sources (official-first)

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