Before you buy any part, work through this. Most of the faults we see are not a dead component — they are a setting, a loose plug, or a brake lever that never came back. This page saves you money, which is why it comes before the shop.
Step 1 — Does the display light up?
Yes, it lights up Power is reaching the system. Go to Step 2.
Nothing at all Check the battery charge, the main power connector, and the fuse. The fault is upstream of the controller.
Step 2 — Does the throttle drive the motor?
Throttle works, but pedalling gives no assist Your battery, controller, motor and main wiring are all fine. The fault is isolated to the pedal-assist chain. Follow the pedal-assist guide →
Display lights but nothing moves Suspect the controller, the motor, the throttle, or a stuck brake cutoff. Work through the table below.
The motor runs on its own Stop. This one is dangerous. Read this before riding again →
Step 3 — Read the error code
If your display shows a code, photograph it. Code tables differ between display models, so the code alone is not enough — but paired with the model number it usually points straight at the fault.
Symptom table
| What you see | Most likely cause | What to do first |
|---|---|---|
| Display on, throttle dead, motor silent | Brake cutoff stuck, throttle failed, or controller failed | Check both brake levers return fully, then test the throttle before suspecting the controller |
| Power there but jerky, stuttering, grinding | Hall sensor fault, or phase and hall wires mismatched | Work through the wiring combinations → |
| Bogs down badly on hills, controller hot | Controller current rating too low, or ageing MOSFETs | Move to a higher-current controller — check your battery BMS can supply it |
| Fine at speed, stutters from standstill | Hall sensors failed, controller running sensorless | Replace the motor, or fit a controller that supports sensorless mode |
Still unsure? Send us four photos
This is how we confirm a fit before you spend anything. Four photos tell us almost everything:
Your display, face on So we can read the model markings.
The display connector, close up Pin count, colour, male or female. This decides whether a part physically plugs in.
Your controller and its label Voltage and current rating are printed on it.
The motor cable where it leaves the axle Counting the wires tells us whether your motor has hall sensors.
Replacing a wheel or motor as well? Also measure the inside width between your rear frame dropouts — it will be 135 mm, 170 mm or 190 mm. How to measure it →
Email them to support@riderow.com and we will tell you which part fits — or tell you that you do not need one.
Not sure what's wrong? Run the three-minute check first — most pedal-assist faults need no new part at all.RideRow sells replacement parts and provides installation information. We do not perform repairs. Installation is carried out by you or a technician you choose.