This article explains how to troubleshoot the E42 Motor Fault Error on an Aventon eBike.

Use this article if your bike:

• Shows an E42 error code
• Has reduced or no motor assistance
• Experiences motor-related warnings
• Has intermittent motor performance issues

If you are unsure of your Aventon model, please confirm your model before continuing.

Stop troubleshooting immediately if anything looks unsafe, damaged, overheated, or if the motor feels resistant or abnormal during use.

Before You Start

Please prepare the following:

• Order number
• Aventon model
• Photo or video of the E42 error code
• Photo of the display
• Photo of the motor cable area
• Photo of accessible motor connectors
• When the issue first appeared
• Whether the bike powers on
• Whether the display turns on
• Whether the motor engages
• Whether the issue happened after transport, storage, water exposure, crash, impact, modification, or third-party repair
• Photos of visible damage

Safety Warnings

• Do not continue riding if the bike has visible damage, overheating, smoke, burning smell, or motor resistance.
• Do not open sealed electrical components.
• Do not work on wiring while the bike is powered on or charging.
• Stop and contact support if you are unsure.

What This Error Means

The E42 Motor Fault Error means the bike has detected a motor-related warning or fault.

This may happen if:

• The motor is damaged
• The motor harness is damaged
• There is a poor connection between the controller and motor
• There is cable or connector damage

Possible Causes

Possible causes include:

• Motor internal warning or error
• Damaged motor
• Damaged motor harness
• Worn cable
• Broken connector
• Internal open circuit
• Visible cable or connector damage
• Damaged controller

Troubleshooting Steps

Step 1 – Inspect the Motor and Motor Harness

Turn the bike off before continuing.

Disconnect, inspect, and clean the accessible:

• Motor connection
• Motor harness
• Motor-to-controller connection

Check for:

• Loose connections
• Bent pins
• Worn cables
• Broken connectors
• Dirt or contamination
• Visible cable damage

Reconnect everything securely and restart the bike.

If yes – Visible damage is found

Continue to the relevant section below:

• Motor damage
• Motor harness damage

If no – No visible damage is found

Fully reconnect the:

• Motor
• Motor harness

Restart the bike and check whether the E42 error remains.

If the issue clears

The issue was likely caused by a loose or poor connection.

Monitor the bike during normal use.

If the issue remains

Continue to Step 2.

Step 2 – Check Whether the Error Persists After Reconnecting

After reconnecting all accessible cables and connectors, restart the bike and test the motor carefully.

If yes – The E42 code still appears

The issue may involve the motor, motor harness, or controller system.

Please contact our support team with the photos/videos listed below so we can review the next step.

If no – The error no longer appears

The issue was likely caused by a temporary connection issue.

Continue monitoring the bike during use.

Visible Damage Troubleshooting

Step 3 – Motor Damage Found

Inspect the motor area for:

• Visible impact damage
• Cracks
• Abnormal motor noise
• Water exposure
• Burning smell

If yes

Do not continue riding the bike.

Please contact our support team with photos/videos of the motor area and error code.

If the issue remains

The motor harness or controller system may also be affected.

Please contact support.

Step 4 – Motor Harness Damage Found

Inspect the accessible motor harness for:

• Cuts
• Worn insulation
• Pinched cables
• Loose connectors
• Bent pins
• Broken fittings

If yes

Do not continue riding the bike.

Please contact our support team with photos of the damaged motor harness and connectors.

If the issue remains

The motor or controller system may also require further inspection.

Please contact support.

Step 5 – Check Whether Motor Problems Continue

Check whether:

• The motor does not engage
• Motor assistance cuts in and out
• The E42 error returns repeatedly
• The motor behaves abnormally during riding

If yes

The issue may involve:

• The motor system
• Motor communication
• The motor harness
• The controller system

Please contact our support team with:

• Video of the issue
• Video of the display during startup
• Photos of accessible motor connectors and wiring

If the issue remains

Please contact support.

Step 6 – Inspect for Visible Controller Damage

Inspect the accessible controller area for:

• Visible damage
• Burn marks
• Loose connectors
• Water exposure
• Damaged cables

If yes

Stop using the bike immediately.

Please contact our support team with photos of the controller area and visible damage.

If no

Restart the bike and check whether the E42 error returns.

If the issue remains

The controller system may require further inspection.

Please contact support.

When To Contact Support

Please contact support if:

• The E42 error remains after completing these checks
• The motor does not engage
• There is visible cable or connector damage
• The bike has abnormal motor behaviour
• The bike has been exposed to water, crash, impact, transport damage, modification, or third-party repair
• You are unsure how to safely complete a step

If the issue remains after these steps, please contact our support team and include the photos/videos listed below.

What To Send Support

Please send:

• Order number
• Aventon model
• Photo/video of the E42 error code
• Photo of the display
• Photo/video of the motor area
• Photo of accessible motor connectors and wiring, if safe
• Photo of the controller area
• Photos of visible damage
• Confirmation of whether the bike powers on
• Confirmation of whether the display turns on
• Confirmation of whether the motor engages
• Confirmation of whether the issue happened after water exposure, crash, impact, modification, or third-party repair
• Confirmation of the troubleshooting steps already completed

Important Safety Notes

• Do not continue riding if the E42 error remains.
• Do not ride the bike if there is visible damage, overheating, smoke, burning smell, or abnormal motor behaviour.
• Do not open the motor, controller, or sealed electrical components.
• Do not force connectors.
• Do not work on wiring while the bike is powered on or connected to the charger.
• Contact support if you are unsure.