Rad Power Bikes display error 24

What Error 24 Means

Error 24 means the controller is not receiving the motor-position signal it expects.

Inside many e-bike motors are small Hall sensors. They tell the controller where the motor is in its rotation so the controller knows when and how to send power.

In plain English, the controller is having trouble figuring out what the motor is doing, so it may stop motor power rather than operate the motor incorrectly.

• Loose or partially seated motor connector

• Water or dirt inside the connector

• Bent or damaged signal pins

Damaged motor wiring

Damage to the cable near the rear axle

Failed Hall sensor inside the motor

Internal motor problem

Controller problem

Before You Touch Anything

Turn the bike off and remove the battery before disconnecting the motor cable. Stop troubleshooting and do not ride the bike if:

• The motor or controller is unusually hot

• You smell something burning

• The motor cable is cut, crushed, or badly damaged

• A connector is melted or burned

The cable where it enters the motor or rear axle is damaged

• The motor suddenly jerks, locks, or behaves unpredictably

1. Restart the Bike

Turn the bike completely off, wait several seconds, and turn it back on. If Error 24 disappears, carefully check whether the motor operates normally. If the error returns, continue below.

2. Inspect the Motor Cable

Turn the bike off and remove the battery. Find the cable coming from the motor and inspect the visible wiring before disconnecting anything.

Where the cable exits the rear axle or motor

Areas where the cable rubs against the frame

Sharp bends

Crushed sections

Cuts or damaged insulation

If the cable is visibly damaged, stop here and have it professionally inspected.

3. Check the Motor Connector

Follow the motor cable until you reach the main motor connector. Pull the two sides straight apart. Do not twist the connector and do not pull on the wires.

4. Inspect the Connector

• Water or moisture

• Dirt or debris

• Bent pins

Damaged or pushed-back pins

• Corrosion

• Burn marks

Melted plastic

Damaged wiring

The smaller signal pins inside the motor connector are especially important for a Hall sensor fault. If anything looks damaged, do not force the connector back together.

5. Reconnect the Motor

If everything looks clean and undamaged, line up the arrows, notches, or alignment marks and push the connector straight together without twisting. Make sure it is fully seated.

6. Carefully Test the Rear Wheel

Before applying any motor power, confirm that the rear drive wheel spins freely by hand. If it binds, locks, or does not spin freely, stop immediately and do not power the motor.

Only perform a wheel-off-ground motor test if the rear wheel can be safely raised and the bike is securely supported. Use a stable bike stand or other manufacturer-appropriate support that keeps the rear wheel clear of the ground.

If using a repair stand, clamp only at a manufacturer-approved clamp point. Never clamp a carbon or thin-wall frame tube merely to perform this test.

Keep hands, clothing, tools, children, and other objects away from the rear wheel. Apply motor power only briefly. The rear wheel should start and spin smoothly.

Stop immediately if the wheel jerks, locks, stutters badly, makes unusual noise, or Error 24 returns.

Error 24 Still Showing?

Failed Hall sensor

Damaged Hall sensor wiring

Internal motor wiring failure

Damaged motor harness

Controller fault

At this point, the motor's Hall sensor circuit should be tested by a qualified e-bike technician. This usually requires electrical testing rather than simply unplugging and reconnecting components.

Quick Answer

Error 24 = motor Hall sensor fault.

The controller is not receiving the motor-position information it expects, so it may shut off motor assistance.

1. Restart the bike.

2. Check the motor cable for visible damage.

3. Inspect the motor connector and its smaller signal pins.

4. Reconnect the connector firmly without twisting.

5. Before any powered test, make sure the rear wheel spins freely by hand.

6. If safely secured with the rear wheel off the ground, briefly test for smooth motor operation.

7. If Error 24 returns, have the Hall sensors, motor wiring, or controller tested.

Do not power the motor if the rear wheel does not spin freely by hand, or if the motor jerks, locks, overheats, smells burned, or has visibly damaged wiring.

Source & Compatibility

KEY-DISP KD21C: Defines Code 24 as "Motor Hall Signal Abnormality." KD21C manual

Rad Power Bikes: Lists Error 24 as "Motor hall fault." Rad support also uses additional motor tests on certain models. Rad owner-manual reference

Error numbers are not universal across all e-bikes. Another display, controller, or motor system may use the same number for a different problem. Confirm the bike's electrical platform before applying this troubleshooting procedure.