Modified on Fri, 12 Dec at 2:20 PM

Troubleshooting | Motor Is Not Responding

When the motor is not responding, it can be caused by several different issues.

In this article: You’ll learn the most common causes of a non-responsive motor and how to quickly troubleshoot them.

This Article Applies to the Following Bikes

Difficulty

★★☆ Medium

Estimated Time

5 – 10 Min

Before You Start

Tools you will need

• Adjustable Wrench (included in your bike tool kit)

• Multitool with Allen Wrenches (included in your bike tool kit)

Preparation

• Turn off your bike.

• Keep the bike stable on the kickstand.

• Make sure the display is fully powered off before unplugging any connectors.

Check the Motor Cable

The main motor cable is responsible for sending power and communication between the motor and the controller. If this connector is loose — even slightly — the motor will not activate, even though the display turns on normally.

Steps

1. Find the main motor plug. A thick round julet connector on the left side near the rear wheel.

2. Pull the connector apart firmly.

3. Reconnect it, aligning the arrows, and push until fully seated.

4. Turn the bike on and test again.

What the results mean

• Motor works again: The connector was loose and is now fixed.

• Still no response: Proceed to the next section.

Check Motor Inhibitors (Brake Sensors)

Your bike has two motor inhibitors (one per brake lever). Their job is to instantly cut motor power when braking.

If they become misaligned, loose, or overly sensitive, the bike may think you’re braking even when you’re not — causing the motor to intermittently cut out or stop responding.

Part A: Disconnect the Brake Sensors

1. Untwist the spiral plastic organizer to expose the cables running down the handlebar.

2. Locate the thin brake-sensor wire coming from each motor inhibitor. Follow the wire down until you find the connector.

3. Disconnect the motor inhibitor’s Julet connector and confirm you see the red interior after separating the plugs.

4. Repeat on the other side.

Part B: Ride Test (Required for Diagnosis)

After disconnecting both brake sensors:

• Ride the bike for 5–10 miles.
  
  

What the results mean

• Motor does NOT cut out at all:
  The brake sensor is the cause and needs adjustment. Continue to Part C.

• Motor still cuts out or doesn’t respond:
  The issue is not the brake sensors. Submit a ticket to MOD Support for further diagnostics.
  
  

Part C: Adjust Both Brake Inhibitors

1. Locate the small set screw and loosen it about two full turns using the smallest (2mm) Allen wrench in your Multitool.

2. Push the cable in and screw in the bolt fully into position so it sits firmly.

3. Re-tighten the set screw.

4. Reconnect both motor inhibitor’s julet connectors, aligning the arrows, and twist the spiral plastic organizers back to cover the cables.

5. Ride your bike again to confirm consistent motor engagement.

If All Else Fails

If:

• The motor cable is connected properly, and

• The motor inhibitors have been tested and adjusted following the 5–10 mile ride test
  
  

…and the motor still cuts out or fails to respond, the issue may involve the controller, throttle signal, pedal-assist sensor, or internal wiring.

Please contact MOD BIKES Support so we can guide you through advanced diagnostics.

Troubleshooting

• Motor cuts in and out during rides → Brake sensor may still be loose. Recheck the set screw.

• Error 25 appears → The brake sensor is activating incorrectly. Perform Step 1B.

• Throttle works only sometimes → Motor cable may not be fully locked; redo Step 2.

FAQs

• Why does disconnecting the brake sensors help?
  Because the motor inhibitors immediately disable the motor if they detect brake activation. Disconnecting them isolates the problem.

• Is it safe to ride with the brake sensors disconnected?
  Only for a short test. Reconnect them after testing for normal safe operation.

• Should both brake sensors be unplugged?
  Yes. Each side has its own sensor and either one can stop the motor.

Warning

⚠️ Important Safety & Liability Notice

These troubleshooting steps are intended as a general guide for MOD BIKES products. Always ensure all connectors and fasteners are properly secured before riding. Improper adjustment may result in damage or injury.

If you are unsure, stop riding immediately and seek help from a qualified MOD BIKES technician. MOD BIKES is not responsible for injury or damage caused by improper maintenance or failure to follow safety guidelines.