eMTB error codes explained
What the error codes on Bosch, Shimano, TQ, Specialized, Yamaha, Giant, Fazua and DJI Avinox systems mean — and what you can check yourself before going to a dealer.
Compiled from manufacturer manuals and support pages (sources under each system). Codes and meanings can change with firmware — the manufacturer’s app or your dealer has the final word.
Bosch smart system (Performance Line CX/CX-R, SX, Performance Line; Kiox 300/500, Purion 200, Nyon, LED Remote / System Controller)
Fault codes appear on the display (Kiox/Nyon/Purion 200) and can be acknowledged with the control-unit button; the eBike Flow app shows the code with a plain-language description. On display-less setups the LED Remote / System Controller signal faults via LEDs and details are read in eBike Flow. Smart-system codes are 6-character (e.g. 523001, 50301E); Bosch publishes each code at bosch-ebike.com/<country>/help-center/error/<code>.
| Code | Meaning | What to do |
|---|---|---|
| 523001 | Drive unit error - sensor system: error in the drive unit's speed sensor. Possible effects: reduced drive unit output, speed display not functional (description as shown in the Bosch app, quoted by owners). | Check speed sensor-to-magnet distance/alignment and the sensor cable; restart. If it persists, dealer replaces sensor/magnet. |
| 503001 | Speed sensor signal missing or invalid (third-party listing). | Check spoke magnet position and speed sensor; restart; dealer if persistent. |
| 503002 | Speed sensor magnet misplaced or tampered (third-party listing). | Re-position the magnet correctly; remove any tuning device; dealer if persistent. |
| 504001 | Speed signal tampering detected, reduced assist (third-party listing). | Remove tuning devices, check magnet; a dealer may be needed to clear it. |
| 510001 | Internal sensor error stalling motor assist (third-party listing). | Restart; dealer diagnosis if it returns. |
| 530001 | Bosch battery authentication fault (third-party listing). | Remove and reinsert battery, restart; dealer if persistent. |
| 532001 | CAN communication fault between drive unit and battery (third-party listing). | Check/clean battery contacts and connections; dealer if persistent. |
| 540022 | Drive unit overheat protection triggered (third-party listing). | Stop, let the drive unit cool, restart. |
| 550350 | Front light failure detected by drive unit (third-party listing). | Check front light and its wiring/connector. |
| 550351 | Rear light defective or not detected (third-party listing). | Check rear light and its wiring/connector. |
| 580001 | Outdated system software detected (third-party listing). | Update via eBike Flow app or have dealer update software. |
| 591001 | Drive unit authentication error (third-party listing). | Restart; dealer diagnosis required if persistent. |
| 53102D | Outdated software detected, motor support off (third-party listing). | Software update via eBike Flow or dealer. |
- First step for nearly every code: switch off, wait, restart without pedalling.
- Look the exact 6-character code up in the eBike Flow app or the Bosch eBike Help Center, which give the official meaning and remedy.
- Speed-sensor/magnet codes (503xxx/504xxx/523001) are the most common rider-fixable faults: check the magnet distance and that nothing has been tampered with.
- Keep the system software current via eBike Flow (OTA).
Motor pages: Bosch Performance Line CX-R, Bosch Performance Line CX Race, Bosch Performance Line CX, Bosch Performance Line SX, Bosch Performance Line PX. Sources: emtbforums.com · ebikecodes.com · help.bosch-ebike.com · simplon.com · bosch-ebike.com
Bosch classic/Active/Performance Line (Gen 2-4, pre-smart system) with Purion, Intuvia, Kiox, Nyon (BUI350)
3-digit fault code shown on the on-board computer (Purion/Intuvia/Kiox/Nyon); the drive may switch off automatically depending on the fault.
| Code | Meaning | What to do |
|---|---|---|
| 410 | One or more buttons of the on-board computer are disabled. | Check whether any buttons are stuck (e.g. dirt); clean them. |
| 414 | Operating unit connection problem. | Have the connections checked. |
| 418 | One or more buttons on the operating unit are disabled. | Check for stuck buttons; clean them. |
| 422 | Drive unit connection problem. | Have the connections checked. |
| 423 | eBike battery connection problem. | Have the connections checked. |
| 430 | Internal battery of the on-board computer is flat (not BUI350). | Charge the on-board computer (in the holder or via USB). |
| 440 | Internal drive unit fault. | Restart the system. If the problem persists, contact your Bosch eBike dealer. |
| 450 | Internal software error. | Restart the system. If the problem persists, contact your Bosch eBike dealer. |
| 500 | Internal drive unit fault. | Restart the system. If the problem persists, contact your Bosch eBike dealer. |
| 502 | Bike light fault. | Check the light and wiring, restart; dealer if it persists. |
| 503 | Speed sensor fault. | Restart the system. If the problem persists, contact your Bosch eBike dealer. |
| 504 | Speed signal distortion detected. | Check spoke magnet position and adjust; check nothing has been tampered with (tuning). Assistance is reduced. |
| 530 | Battery fault. | Switch off, remove and reinsert the battery, restart; dealer if it persists. |
| 540 | Temperature error (outside permissible range). | Switch off and let the drive unit cool down or warm up, restart; dealer if it persists. |
| 550 | An impermissible load has been detected. | Remove the load, restart; dealer if it persists. |
| 591 | Authentication error. | Switch off, remove and reinsert battery, restart; dealer if it persists. |
| 605 | Battery temperature error. | Let the battery cool down/warm up to permissible range, restart; dealer if it persists. |
| 620 | Charger fault. | Replace the charger; contact your Bosch eBike dealer. |
| 656 | Software version error. | Contact your Bosch dealer for a software update. |
| 7xx | Error relating to third-party components (e.g. gear hub). | See the component manufacturer's operating instructions. |
- Most codes: restart the system first; if the code returns, see a Bosch dealer.
- Connection codes (414/422/423/424) usually mean a plug or cable problem - have them checked rather than opening components.
- Display blank = internal fault of on-board computer: switch system off and on.
Motor pages: Bosch Performance Line CX. Sources: terratrike.com · bike-magazin.de
Shimano STEPS / Shimano EP (EP8/EP801, EP6/EP600, E-series)
Error codes 'E***' and warning codes 'W***' on the cycle computer screen (e.g. SC-EM800, SC-EN600); newer firmware can show 5-digit variants (e.g. W10000, E01000). Shimano's official code lookup is si.shimano.com/en/error.
| Code | Meaning | What to do |
|---|---|---|
| W010 | High temperature detected in the drive unit (assist may be reduced). | Let the motor cool; check brakes aren't rubbing; avoid long Boost/hard-gear efforts in heat. |
| W011 | Traveling speed cannot be detected (speed sensor signal lost). | Check speed sensor wiring and sensor-magnet distance; dealer if persistent. |
| W013 | Torque sensor initialization not completed successfully (often when powering on with a foot on the pedal). | Take your foot off the pedal and restart the system. |
| W020 | Battery temperature outside operating range. | Let the battery warm up or cool down. |
| W031 | Chain tension or crank installation issue. | Have crank/chain installation corrected. |
| W032 | Electronic rear derailleur / shifter configuration issue. | Check installation / install a compatible shifting unit. |
| E010 | Abnormality detected in the drive unit / system error. | Restart; check E-TUBE cables and ports for damage/corrosion; check for firmware updates; dealer if persistent. |
| E013 | Abnormality detected in the drive unit firmware. | Update/reinstall firmware via E-TUBE PROJECT (app or dealer). |
| E014 | Speed sensor possibly installed in the wrong position / signal abnormality. | Check sensor and magnet positioning; dealer if persistent. |
| E020 | Communication error between battery and drive unit. | Check power cable and battery mount/contacts (remove battery before cleaning); dealer. |
| E021 | Connected battery not supported. | Remove, restart, reinstall battery; use a compatible battery; consult dealer. |
| E022 | Non-conforming battery connected. | Use a standards-compliant Shimano battery; dealer. |
| E033 | Firmware compatibility error. | Install appropriate firmware via E-TUBE PROJECT. |
| E299 | Drive unit entered Safe Mode because tampering was detected. | Remove tuning devices; dealer needed. |
- W-codes are warnings that usually clear on their own; E-codes stop assist and usually need a restart or dealer.
- Never power on while pressing on a pedal (triggers W013).
- Keep all components on matching firmware via E-TUBE PROJECT Cyclist.
Motor pages: Shimano EP8 / EP801 / EP6. Sources: si.shimano.com · merida-bikes.com · emtbforums.com · bike-magazin.de · manualslib.com
DJI Avinox (M1, M2, M2S) with Avinox control displays
No public numeric error-code table. A warning appears on the control display; swipe up > Settings > System Status shows the warning details and troubleshooting. Logs are exported in the Avinox Ride app (Help > Support > Drive System Errors) and sent to the bike manufacturer. Charger LED: solid/flashing yellow (or off) = abnormal protection state.
| Code | Meaning | What to do |
|---|---|---|
| Charger LED solid/flashing yellow or off | Charger is in an abnormal protection state (solid yellow is normal with no battery connected). | Stop charging immediately and contact the bike manufacturer. |
- Read the warning in Settings > System Status on the display.
- If the issue persists, contact the bike manufacturer (not DJI directly) and export the drive-system log from the Avinox Ride app.
- Keep firmware updated through the app.
Motor pages: DJI Avinox. Sources: dl.avinox-ebike.com · bike-magazin.de
TQ HPR50 (also HPR40/HPR60 systems) with Display V01/V02 and Remote
Code on the top-tube display as 'ERR'/'WRN' + 4-character hex code + component label (DRV = drive unit, BATT = battery, SPD SENS = speed sensor, DISP = display). Since the July 2025 app update, error codes are also shown in the TQ E-Bike app.
| Code | Meaning | What to do |
|---|---|---|
| ERR 0401 DRV SW | General software error. | Restart the system. Contact your TQ dealer if the error still occurs. |
| ERR 0403 DRV COMM | Peripheral communication error. | Restart the system. Contact your TQ dealer if the error still occurs. |
| ERR 0440 DRV HW | Drive unit electronic error. | Restart the system and avoid unintended use. Contact your TQ dealer if the error still occurs. |
| ERR 0451 DRV HOT | Drive unit over-temperature error. | Permissible temperature exceeded or fallen below: switch off to let the drive cool, restart; dealer if it persists. |
| ERR 047F DRV HOT | Drive unit overtemperature error. | Switch off to let the drive cool down, restart; dealer if it persists. |
| ERR 0480 DRV SENS | Drive unit assist error. | Restart the system and avoid unintended use. Contact your TQ dealer if the error still occurs. |
| ERR 0481 BATT COMM | Battery communication error. | Restart the system. Contact your TQ dealer if the error still occurs. |
| ERR 049C DRV SENS | Torque sensor error. | Restart the system and avoid unintended use. Contact your TQ dealer if the error still occurs. |
| ERR 04A0 DRV COMM | CAN-bus communication error. | Check the charging port for dirt; restart; dealer if it persists. |
| ERR 04A8 SPD SENS | Speed sensor error. | Check the magnet-to-sensor distance or check for tampering. |
| ERR 04B0 DRV HW | Drive unit mechanical error. | Check if anything is stuck or wedged in the chainring; dealer if it persists. |
| WRN 0601 SPD SENS | Speed sensor problem. | Check magnet-to-sensor distance, restart; dealer if it persists. |
| WRN 0602 DRV HOT | Drive unit overtemperature. | Switch off to cool down, restart; dealer if it persists. |
| WRN 0603 DRV COMM | CAN-bus communication problem. | Check the charging port for dirt, restart; dealer if it persists. |
| WRN 0604 DRV UPDT | Encoder update from torque sensor. | Wait approx. 1 minute without switching off. |
| ERR 4409 BATT HW | Battery deep discharged or defective cell. | Recharge the battery immediately, restart; dealer if it persists. |
| ERR 440A BATT UV | Battery voltage too low. | Recharge the battery immediately; dealer if it continues. |
| ERR 441C BATT HOT | Battery cell temperature too high. | Let the battery cool to room temperature, restart; dealer if it persists. |
| ERR 5402 DISP BTN | Remote button pressed when switching on. | Don't press the remote during start-up; check for buttons stuck with dirt and clean. |
| WRN 5404 DISP BTN | Walk assist user error. | Press UP (Walk) until 'Walk' appears, release, then press again to use walk assist. |
- Most TQ codes: restart; if it recurs, contact a TQ dealer.
- CAN-bus codes often come from a dirty charging port - clean and dry it.
- Speed-sensor codes: check magnet distance first.
Motor pages: TQ HPR50 / HPR60. Sources: tq-ebike.com · tq-ebike.com · tq-ebike.com · manuals.plus
FAZUA Ride 60 (LED Hub / Ring Control)
No numeric codes for riders: faults are shown by LED blink patterns on the top-tube LED hub/ring; diagnostics via FAZUA Toolbox (USB-C) at home or dealer.
| Code | Meaning | What to do |
|---|---|---|
| All LEDs flash yellow 3x (every 10 s) | Soft fault: temporary or non-critical malfunction, in most cases loss of support; commonly speed-sensor related. | Check speed sensor/magnet, restart; have it checked by a dealer if it repeats. |
| All LEDs flash red 3x (every 3 s) | Hard fault: bike can no longer be operated. | Must be serviced at a specialized FAZUA workshop. |
| Bottom LED pulses in support-mode colour | Battery state of charge below 10%. | Charge soon. |
| Bottom LED flashes white | Battery depleted. | Recharge the battery. |
- Speed-sensor issues are the most common cause of the yellow soft fault.
- Install the latest Firmware Bundle via FAZUA Toolbox before troubleshooting further.
Motor pages: Fazua Ride 60. Sources: fazua.com · dealer.fazua.com
Specialized Turbo (Levo, Kenevo, Vado, Creo, Como; TCU, TCD-w, MasterMind TCU/TCD)
Text error messages on the TCU/TCD display (older TCU shows numbered errors 1-7); the Mission Control / Specialized app translates live errors into 'User Actions' and can upload an 'Advanced Diagnostic' report for the retailer, who reads the Event Log in Turbo Studio.
| Code | Meaning | What to do |
|---|---|---|
| 1. BATTERY ERROR (TCU) | Battery component error. | Reboot; check Mission Control app; contact an authorized Specialized retailer if it persists. |
| 2. BATTERY NOT FOUND (TCU) | Battery not communicating (usually a lost connection/loose connector). | Reboot; check Mission Control; retailer if persists. |
| 3. MOTOR ERROR (TCU) | Motor component error (a missing speed sensor magnet can also trigger it). | Reboot; check Mission Control; retailer if persists. |
| 4. MOTOR NOT FOUND (TCU) | Motor not communicating (connector/cable). | Reboot; check Mission Control; retailer if persists. |
| 5. BATTERY & MOTOR ERROR (TCU) | Battery and motor error. | Contact your authorized Specialized retailer. |
| 6. TCU COIN CELL BATTERY LOW | TCU coin cell low. | Replace the coin cell battery in the TCU. |
| 7. RANGE EXTENDER ERROR | Range extender fault. | Check the RE plug is inserted and locked; check for water in the plug; retailer if persists. |
| LOW BATT / LO BAT (TCD-w) | TCD-w CR1220 coin cell low (only the clock setting is lost). | Replace the CR1220 coin cell. |
| NO MOTOR (MasterMind) | Motor not found - communication/connection issue. | Reboot; check connectors; Mission Control; retailer. |
| MOTOR ERROR (MasterMind) | Motor component error. | Reboot; Mission Control User Actions; retailer. |
| NO BATTERY (MasterMind) | Battery not found - communication/connection issue. | Reboot; check connectors; retailer. |
| BATT ERROR (MasterMind) | Battery component error. | Reboot; Mission Control; retailer. |
| RADAR ERROR (MasterMind) | Error from connected radar device. | Reboot; Mission Control; retailer. |
| GEAR SHIFTER ERROR (MasterMind) | Error from the gear shifter component. | Reboot; Mission Control; retailer. |
| TAMPER ERROR (MasterMind) | Tamper error message shown by the system. | Contact retailer. |
- 'Not found'/'No xy' messages are usually loose or damaged connectors/cables; 'error' messages need further investigation and possibly parts.
- Many TCU2/MasterMind errors can be cleared with a remote button press; restart if it persists - the bike stays rideable without assist.
- Use Mission Control's diagnostic report so the retailer can read the event log.
Motor pages: Specialized Turbo motors. Sources: support.specialized.com · content.specialized.com · content.specialized.com · content.specialized.com · manualslib.com
Yamaha e-Bike Systems (PW series, PW-X2/X3, PW-S2 drive units)
Numeric error code on the display unit ('The display indicates an error code'); some displays show text such as 'SPD SNSR / CHK MAGNET'. Battery capacity LEDs flashing (alternately/simultaneously) indicate battery or charger faults.
| Code | Meaning | What to do |
|---|---|---|
| 12 | Display unit: communications to the display stopped. | Check the display connector; dealer may replace display, wire lead or controller. |
| 13 | Drive unit-display communication data failure. | Make sure drive unit and display unit combination is correct. |
| 31 | Torque sensor: no signal / disconnected / short-circuit / wiring failure. | Cycle power; dealer replaces torque sensor or controller if it persists. |
| 33 | Torque sensor: abnormal no-load voltage. | Cycle power; dealer may adjust torque-sensor reference voltage or replace parts. |
| 38 | Crank sensor: abnormal U-phase current sensor voltage while motor not operating. | Cycle power; dealer replaces sensor/controller/drive axle if persistent. |
| 61 | Controller: over-current on motor phase. | Cycle power; dealer replaces controller/drive unit if persistent. |
| 62 | Motor: abnormal phase current (does not clear on power cycle). | Dealer replaces controller or drive unit. |
| 64 | Controller: circuit board temperature too low (-20 °C) or too high (125 °C). | Cycle power once temperature is normal; dealer if it repeats. |
| 66 | Controller: EEPROM error. | Cycle power; dealer if persistent. |
| 68 | Encoder: disconnected or short-circuited lead. | Dealer checks encoder connector/wire, controller or motor. |
| 71 | Battery: can't receive data from battery correctly. | Check battery-bike connection and charging connector; dealer. |
| 73 | Battery: detected voltage too high (45 V). | Dealer check of receptacle, wiring, controller, battery. |
| 79 | DC/DC converter: abnormal DC current. | Dealer replaces DC/DC converter or controller. |
| SPD SNSR / CHK MAGNET | Speed sensor or spoke/brake-disc magnet issue (speed sensor disconnected). | Check speed sensor connector and sensor-magnet gap (5-17 mm per Yamaha manual); replace sensor set if needed. |
- Many Yamaha errors clear when power is cycled; if the same error recurs it may not clear and needs a dealer.
- Both battery capacity LEDs flashing simultaneously = battery protection activated; have the battery replaced at a dealer.
Motor pages: Yamaha PW-X3. Sources: cdn2.yamaha-motor.eu · bike-magazin.de
Giant SyncDrive (Pro/Sport/Life) with RideControl Ergo/Go/Evo, RideDash Evo, SmartGateway
No numeric codes in Giant's current manual. RideControl remotes: lighting indicator flashes red and one assist LED (F1-F5) blinks; RideControl Go: all assist LEDs blink white 3x then one LED (B1-B5) blinks red; RideDash Evo: warning screen (2 s) + event description (5 s), then a wrench service icon in the status bar.
| Code | Meaning | What to do |
|---|---|---|
| LED 1 blinking (F1/B1) | Battery (EnergyPak) issue. | Switch off, check obvious causes (e.g. reseat incorrectly placed battery), switch on; dealer if it persists. |
| LED 2 blinking (F2/B2) | Motor (SyncDrive) issue. | Switch off/on; if it returns, stop riding and contact an authorized dealer. |
| LED 3 blinking (F3/B3) | Speed sensor issue. | Check sensor/magnet, restart; dealer if persistent. |
| LED 4 blinking (B4, RideControl Go) | Smart Gateway / remote / display error. | Restart; dealer if persistent. |
| LED 5 blinking (F5/B5) | Heat issue / motor overheated. | Let the motor cool, restart. |
| Wrench icon (RideDash Evo) | Service due or a system event has occurred. | Note the event description; restart; schedule dealer service. |
- Giant's procedure: note the indicator, switch off, check for obvious causes, switch back on; if solved, still schedule a dealer check; if it persists, stop riding and see an authorized dealer.
Motor pages: Giant SyncDrive. Sources: static.giant-bicycles.com
FAQ
What should I do first when my eMTB shows an error code?
Note the code, switch the system off, check the obvious causes (speed sensor magnet, battery seated and charged, cable plugs), then switch it on again. Many codes clear after a restart. If the code returns, contact your dealer — most motor and battery faults need the manufacturer’s diagnostic software.
Can I clear eMTB error codes myself?
Temporary faults usually clear with a restart. Stored fault logs and motor or battery errors can only be read and reset by a dealer with the manufacturer’s tool (for example Bosch DiagnosticTool, Shimano E-Tube Project Professional or the Specialized/TQ service software).
Why does my speed sensor error keep coming back?
Speed sensor errors are the most common eMTB codes. They are usually caused by a moved or missing spoke or disc magnet, a sensor knocked out of position, or a damaged cable. Check the gap and alignment specified by the manufacturer.