This article explains how to troubleshoot the E43 Battery Fault Error on an Aventon eBike.

Use this article if your bike:

• Shows an E43 error code
• Has a battery fault warning
• Powers on but shows a battery communication issue
• Has intermittent power or display issues related to the battery system

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

Stop troubleshooting immediately if anything looks unsafe, damaged, overheated, wet, or smells burnt.

Before You Start

Please prepare the following:

• Order number
• Aventon model
• Photo or video of the E43 error code
• Photo of the display
• Photo of the battery area
• Photo of the charger and charger light, if relevant
• When the issue first appeared
• Whether the bike powers on
• Whether the battery charges
• Whether the display turns on
• Whether the issue happened after charging, riding, transport, storage, water exposure, crash, impact, modification, or third-party repair
• Photos of any visible damage

Safety Warnings

• Do not continue riding if the bike has visible damage, overheating, smoke, water exposure, or a persistent error code.
• 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 E43 error means the bike has detected a battery fault or communication issue between the battery and display system.

This may involve the battery, terminal, display harness, or related connections.

Possible Causes

Possible causes include:

• Battery internal warning or fault
• Damaged battery
• Damaged cable between the battery and display
• Worn cable
• Broken connector
• Internal open circuit
• Damaged display
• Damaged display harness
• Damaged terminal
• Visible impact or connector damage

Troubleshooting Steps

Step 1 – Inspect the Battery Terminal and Display Harness

Turn the bike off before continuing.

Disconnect and inspect the following accessible areas:

• Battery terminal
• Display harness connection
• Visible connectors

Check for:

• Dirt or contamination
• Loose connections
• Bent pins
• Visible cable damage
• Broken connectors
• Signs of impact or wear

If safe to do so, clean accessible terminals and reconnect everything securely.

Restart the bike.

If yes – Visible damage is found

Continue to the relevant section below:

• Display damage
• Display harness damage
• Terminal damage
• Battery damage

If no – No visible damage is found

Fully reconnect:

• Display
• Battery
• Terminal
• Display harness

Restart the bike and check whether the E43 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 components, restart the bike and check the display again.

If yes – The E43 code still appears

The issue may involve the display or display harness.

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.

Monitor the bike during charging and riding.

Visible Damage Troubleshooting

Step 3 – Display Damage Found

Check whether the display housing, screen, or visible display wiring is damaged.

If yes

Do not continue riding the bike.

Please contact our support team with photos of the display and error code.

If the issue remains after the display is inspected

The display harness or battery system may also be affected.

Please contact support.

Step 4 – Display Harness Damage Found

Check whether the display harness has:

• Visible wear
• Cuts
• Pinched sections
• Broken connectors
• Loose fittings

If yes

Do not continue riding the bike.

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

If the issue remains

The display or battery system may also be affected.

Please contact support.

Step 5 – Terminal Damage Found

Inspect the accessible battery terminal area for:

• Bent pins
• Corrosion
• Loose connections
• Physical damage

If yes

Do not continue riding the bike.

Please contact our support team with photos of the terminal area.

If the issue remains

The display, harness, or battery system may also require further inspection.

Please contact support.

Step 6 – Battery Damage Found

Inspect the battery for:

• Cracks
• Swelling
• Impact damage
• Water exposure
• Burning smell
• Overheating
• Charging problems

If yes

Stop using the bike and battery immediately.

Do not continue charging or riding the bike.

Please contact our support team with photos/videos of the battery and charger.

If the issue remains

Please contact support for further assessment.

When To Contact Support

Please contact support if:

• The E43 error remains after completing these checks
• The bike does not power on
• The display does not power on
• The battery does not charge
• There is visible damage
• There are damaged connectors, terminals, or cables
• The bike has been exposed to water, 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 E43 error code
• Photo of the display
• Photo of the battery area
• Photo of the charger and charger light, if relevant
• Photo of accessible connectors or terminals, if safe
• Photos of visible damage
• Confirmation of whether the bike powers on
• Confirmation of whether the battery charges
• Confirmation of whether the display turns on
• Confirmation of whether the issue started after charging, riding, storage, transport, 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 E43 error remains.
• Do not ride the bike if there is visible damage, overheating, smoke, burning smell, or water exposure.
• Do not open the battery, 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.