Aventon Mid-Drive Bikes – E48 Turn Light Fault TroubleshootingUpdated 2 days ago
This article explains how to troubleshoot the E48 “Turn Light Fault” error on Aventon mid-drive bikes.
Use this article if your bike:
- Shows error code E48
- Displays “Turn Light Fault”
- Has turn signal performance issues
- Experiences intermittent turn signal operation
- Turn signals do not function properly
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 E48 error code
- when the issue first appeared
- whether the bike powers on
- whether the battery charges
- whether the display turns on
- whether the motor engages
- whether the turn signals function correctly
- 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 turn signals are not functioning properly.
- Do not continue riding if the bike has visible damage, overheating, smoke, burning smell, 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
E48 indicates a turn light fault involving the taillight or rear light harness system.
The issue may be caused by:
- a damaged turn signal light
- damaged rear light wiring
- communication or power issues between the turn lights and mid-drive unit
Possible Causes
- damaged turn signal light
- damaged taillight
- damaged rear light harness
- damaged cable between the rear lighting system and mid-drive unit
- worn cable
- broken connector
- internal open circuit
Troubleshooting Steps
Step 1 – Disconnect, Inspect, and Clean the Rear Lighting Components
Disconnect, inspect, and clean:
- taillights
- rear light harness
- rear light connections to the mid-drive unit
Ensure there are no obvious signs of damage.
After reconnecting all components, restart the bike and check whether the E48 code remains.
If the issue clears
The issue was likely caused by a loose or dirty connection.
If the issue remains
Inspect the taillights and rear light harness for visible damage.
Step 2 – Inspect for Visible Damage
Inspect the following components for visible damage:
- taillights
- rear light harness
If the taillights are damaged
Replace the taillights.
After replacement, restart the bike and check whether the E48 code remains.
If the rear light harness is damaged
Replace the rear light harness.
After replacement, restart the bike and check whether the E48 code remains.
If the issue clears
The issue was likely caused by the damaged component that was replaced.
If the issue remains
Replace the remaining rear lighting communication component.
Step 3 – Replace the Rear Light Harness
Replace the rear light harness if:
- the issue remains after replacing the taillights
- the harness shows visible damage
- communication or lighting issues continue after reconnecting components
After replacement, restart the bike and check whether the E48 code remains.
If the issue clears
The issue was likely caused by a faulty rear light harness.
If the issue remains
Replace the taillights.
Step 4 – Replace the Taillights
Replace the taillights if:
- the issue remains after replacing the rear light harness
- the taillights show visible damage
- the turn light fault continues after reconnecting components
After replacement, restart the bike and check whether the E48 code remains.
If the issue clears
The issue was likely caused by faulty taillights.
If the issue remains
Replace both the taillights and rear light harness.
Step 5 – Replace the Taillights and Rear Light Harness
Replace:
- the taillights
- the rear light harness
After replacement, restart the bike and check whether the E48 code remains.
If the issue clears
The issue was likely caused by a communication failure between the rear lighting system and harness.
If the issue remains
Replace the mid-drive unit.
Step 6 – Replace the Mid-Drive Unit
Replace the mid-drive unit if:
- the issue remains after replacing the taillights
- the issue remains after replacing the rear light harness
- the issue remains after replacing both the taillights and harness
- communication issues continue after all previous troubleshooting steps
After replacement, restart the bike and check whether the E48 code remains.
If the issue clears
The issue was likely caused by a faulty mid-drive unit.
If the issue remains
Please contact support for further diagnosis.
When To Contact Support
Please contact support if:
- the E48 error remains after completing the steps above
- there is visible damage
- the battery does not charge
- the bike does not power on
- the display does not power on
- the motor does not engage
- the turn signals do not function correctly
- the issue appears related to the taillights, rear light harness, connectors, mid-drive unit, or internal wiring
- 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
- 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 E48 error code
- photo of the display
- photo of the rear lighting area
- photo of accessible connectors or harnesses, 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 motor engages
- confirmation of whether the turn signals turn on or flicker
- confirmation of whether there was water exposure, crash, impact, modification, or third-party repair
- list of troubleshooting steps already completed
Important Safety Notes
- Do not continue riding if the E48 error remains or the turn signals do not function properly.
- Do not ride in traffic conditions without functioning turn signals if required for safe operation.
- Do not ride if there is visible damage, overheating, smoke, burning smell, water exposure, or motor resistance.
- Do not open the battery, controller, display, mid-drive unit, 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.