Reference

Rad Power Bikes error codes by display

What Rad Power Bikes error codes mean on the Color Display, Rad UI remote and display, and older LCD and LED displays, using only codes from Rad's official support pages, with safe checks for each.

Last edited Nov 8, 2026 by Pedalwise team Edit History Add a subpage

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Battery and electrical safety. Lithium-ion batteries can catch fire if they're damaged or charged wrong. Never open a battery pack, and stop using any battery that's swollen, hot, wet or smells burnt. Every edit to this page is checked by a second person before it goes live.

Rad Power Bikes error codes depend on which display your bike has, so the same number can come with different advice. This page lists only codes stated on Rad's official support pages, grouped by display, with what you can safely check. If your code isn't here, look it up on Rad's support site for your exact model.

Before you start

Write down the number or take a photo of the display.
Turn the bike off and back on. Don't hold a brake lever, the throttle or another button while it powers up. Several codes come from exactly that.
Before touching any connector, power off, remove the battery and drain leftover power by holding the power button, as Rad's guides direct.
Pull connectors straight apart and push them straight together with the notch, pins and arrows lined up. Never twist.
Rad warns not to put tools into connectors, not to straighten bent pins, and not to clean or repair damaged, dirty or wet contacts. Photograph them and contact Rad support instead.

Color Display codes

Rad's Color Display error codes page covers the Radster Trail, Radster Road, RadExpand 5 Plus and RadWagon 5.

6: battery undervoltage. Charge the battery fully.
10: battery overvoltage. Restart, and use only a Rad approved battery.
12: motor stall warning, such as light throttle on a steep hill or throttle with the brakes on. Restart, and don't use the throttle against the brakes.
15: torque sensor error. Rad suggests checking the torque sensor connector for moisture or damage. Have a shop do this if you aren't comfortable at the controller.
16: controller error. Restart. If it stays, a connector check or a shop is next.
17: throttle on at startup. Let go of the throttle while powering on.
21: abnormal motor current. Power off and let the motor cool.
22: throttle fault. Inspect the throttle connector for moisture or damage.
23: motor phase fault, often after heavy climbing. Let the motor cool. If it happens on flat ground, contact Rad support.
24: motor hall fault. Inspect the motor cable connector for moisture or damage.
25: brake switch fault. Release the brake levers while powering on.
30: communication error between controller and display. Follow Rad's error 30 connector guide for your model.
34: stuck button. Release the power button once the bike starts, and free any stuck button.

Rad UI remote codes (RadTrike)

On the RadTrike, Rad's RadTrike error codes page explains that the remote shows a large E with power bars. The lower bars give the first digit and the top bars give the second. Error 30 can also look like a single flashing bar, which is easy to mistake for low battery.

21: abnormal current between battery and controller. Power cycle the trike.
22: throttle fault.
23: motor phase wire problem.
24: motor connector problem.
25: brake switch fault. Release the hand brake when powering on.
30: connection fault somewhere on the trike. Treat it as a connection error if the battery itself shows charge.
31: power fault, often from holding the power button more than six seconds or a stuck button.

Rad UI display and remote: error 31

Rad's error 31 guide calls it a power button failure. Release the button as soon as the display lights up, and check the remote's button isn't stuck. If it continues, photograph the remote and display and contact Rad support.

LCD and LED displays

On older bikes, the LCD display shows the number. The LED display flashes pedal assist level lights instead.

22: throttle issue. On LED displays, level 1 flashes. See Rad's error 22 guide.
23: motor phase wires. On LED displays, levels 0 and 1 flash. See Rad's error 23 guide.
24: motor hall sensor fault. On LED displays, level 2 flashes. Rad's error 24 guide includes a connector check and a throttle test with the wheel off the ground, then asks you to send results to support.
30: communication error. On the RadRunner and RadExpand, all pedal assist lights may flash or the bike may not power on.

Error 30 connector checks

Rad has a separate error 30 guide for each model. The RadRunner and RadExpand guide checks the battery terminals first, then front connectors one at a time in order: display, brake levers, throttle, headlight, motor and taillight, testing after each. The RadCity 5 Plus guide follows the same idea for the Rad UI bikes. Find your model under Rad's maintenance and troubleshooting hub.

When to get a pro

Connectors under the skid plate or the harness inside the downtube.
Any code that returns after a restart and the simple connector checks.
Moisture, corrosion or damage on any connector or battery terminal.

Error codes about the battery, controller or motor wiring can point to a real electrical fault. Don't keep riding with a repeating code, and never open the battery or controller. Take it to a qualified shop or contact Rad support. See e-bike error codes and e-bike battery care.

Sources

Stuck after these checks? Find a shop near you.

Need a pro?

If these steps didn't fix it, find a shop near you in our partner network. For battery or wiring trouble, look for shops marked Battery and electrical.

Talk

Questions, things that worked for you, or something that looks wrong on this page.

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