Aventon Mid-Drive Bikes – W04 Low Temperature Charging Protection TroubleshootingUpdated a day ago

This article explains how to troubleshoot the W04 “Low Temperature Charging Protection” warning on Aventon mid-drive bikes.

Use this article if your bike:

• Shows warning code W04
• Displays “Low Temperature Charging Protection”
• Will not charge in cold temperatures
• Stops charging unexpectedly
• Displays charging protection warnings during winter or cold-weather storage

If you are unsure about any step or notice anything unsafe, stop troubleshooting and contact support.

Before You Start

Please prepare the following:

• order number
• Aventon model
• photo or video of the issue
• photo of the W04 warning code
• current ambient temperature
• whether the battery powers the bike normally
• whether the charger indicator lights behave normally
• whether the battery was stored in cold conditions
• whether the issue began after transport, storage, water exposure, crash, impact, modification, or third-party repair
• photos of any visible battery or charger damage

Safety Warnings

• Do not charge a frozen or extremely cold battery.
• Do not expose the battery to direct heat sources to warm it quickly.
• Do not use damaged chargers or batteries.
• Stop immediately if the battery becomes swollen, excessively hot, leaks, smokes, or emits unusual odors.
• Only use Aventon-approved chargers and batteries.

What This Warning Means

W04 indicates the battery temperature is too low for safe charging.

The battery management system automatically blocks charging in low temperatures to prevent battery damage.

Possible Causes

• ambient temperature is below the safe charging range
• battery temperature is too cold
• battery was stored outdoors or in freezing conditions
• damaged battery

Troubleshooting Steps

Step 1 – Warm the Battery to a Safe Temperature

Stop charging immediately.

Move the battery to an indoor environment between:

• 32°F–113°F (0°C–45°C)

Allow the battery to warm for at least 2 hours.

After warming:

1. Reconnect the charger
2. Attempt to charge the battery again
3. Check whether the W04 warning remains

If the issue clears

The warning was caused by low battery temperature.

To help prevent future charging interruptions:

• store the battery indoors during cold weather
• allow cold batteries to warm before charging
• avoid charging immediately after freezing exposure
• avoid leaving batteries in vehicles or outdoor environments during winter

If the issue remains

Proceed with battery replacement.

Step 2 – Replace the Battery

Replace the battery if:

• the W04 warning remains after warming the battery
• charging protection occurs repeatedly in normal indoor temperatures
• the battery will not charge
• charging stops unexpectedly
• there are signs of battery damage

After replacement:

1. Connect the charger
2. Verify charging begins normally
3. Confirm the W04 warning no longer appears

If the issue clears

The issue was likely caused by a damaged battery.

If the issue remains

Please contact support for additional diagnosis.

When To Contact Support

Please contact support if:

• the W04 warning remains after completing the steps above
• the battery will not charge indoors at normal room temperature
• the charger indicator behaves abnormally
• the battery becomes swollen, excessively hot, leaks, smokes, or emits odor
• the issue appeared after water exposure, crash, impact, modification, or third-party repair
• you are unsure how to safely complete a step
• you need warranty, repair, replacement part, refund, or replacement support

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

What To Send Support

Please send:

• order number
• Aventon model
• photo or video of the W04 warning code
• photo of the display
• photo or video showing the charging issue
• current ambient temperature
• confirmation of whether the battery powers the bike normally
• confirmation of whether the charger indicator lights behave normally
• confirmation of whether the battery was exposed to freezing temperatures
• confirmation of whether there was water exposure, crash, impact, modification, or third-party repair
• photos of the battery and charger
• list of troubleshooting steps already completed

Important Safety Notes

• Never charge a frozen battery.
• Always allow cold batteries to warm gradually before charging.
• Only use Aventon-approved chargers and batteries.
• Stop using the battery immediately if there are signs of swelling, smoke, leakage, odor, or overheating.
• Contact support if you are unsure.