Aventon Mid Drive – Brake Sensor Adjustment TroubleshootingUpdated 2 days ago
This article explains how to troubleshoot and adjust the brake sensor sensitivity on Aventon mid drive eBikes.
Use this article if your bike:
cuts motor power unexpectedly while riding
shows Error 25 on the display
shows Error 26 on the display
does not provide motor assistance correctly
continues providing motor assistance after releasing the brake lever
loses motor assistance while riding without braking
Brake sensors are an important safety feature. If you are unsure about any step or notice damaged components, stop and contact support before continuing.
Before You Start
Please prepare the following:
order number or proof of purchase
Aventon model
photo or video of the issue
photo of any error code shown on the display
confirmation of whether the bike powers on
confirmation of whether the display turns on
confirmation of whether the motor engages
details about when the issue first appeared
confirmation of whether the issue happened after transport, storage, impact, crash, modification, or third-party repair
photos of any visible damage near the brake levers or wiring
Safety Warnings
Do not continue riding if the bike behaves unpredictably while braking.
Do not ride if the motor continues engaging while braking.
Do not open sealed electrical components.
Do not force connectors or adjustment screws.
Do not work on wiring while the bike is powered on or charging.
Stop and contact support if you are unsure.
What This Issue Means
Brake sensors help disable motor power when the brake lever is pulled.
If the brake sensor sensitivity is incorrect:
the motor may cut out unexpectedly
the bike may display Error 25 or Error 26
the motor may not disengage correctly while braking
Correct brake sensor adjustment helps ensure the bike operates safely.
Possible Causes
Possible causes include:
brake sensor sensitivity set incorrectly
disconnected brake sensor connection
damaged brake sensor wiring
loose connector
brake lever position issue
visible cable damage
brake sensor communication issue
Troubleshooting Steps
Step 1 – Check for Error Codes
Turn the bike on and check the display.
Look for:
Error 25
Error 26
If yes
Continue to Step 2.
If no
Continue to Step 2 if the bike is still showing brake-related symptoms.
If the issue clears
Monitor the bike during future rides.
If the issue remains
Continue to the next step.
Step 2 – Check the Brake Lever Operation
With the bike powered on:
gently pull and release each brake lever
check whether the motor cuts out correctly when braking
check whether the motor resumes normally after releasing the brake
If yes
If the motor operation seems inconsistent:
continue to Step 3
If no
If the motor does not disengage correctly while braking:
continue to Step 3
If the issue clears
The issue may have been temporary.
If the issue remains
Continue to Step 3.
Step 3 – Inspect Visible Brake Sensor Connections
Power the bike off before continuing.
Inspect the visible brake sensor wiring near the brake levers.
Check for:
loose visible connectors
disconnected wiring
bent pins
damaged cables
pinched wiring
impact damage
Only inspect accessible external areas.
If yes
If visible damage or disconnected wiring is found:
do not continue riding
contact support with photos/videos listed below
If no
Continue to Step 4.
If the issue clears
The issue may have been caused by a loose visible connection.
If the issue remains
Continue to Step 4.
Step 4 – Locate the Brake Sensor Adjustment Area
Identify the brake lever style installed on the bike.
The brake sensor adjustment area may be:
underneath the brake lever
on top of the brake lever housing
near the brake sensor cable entry point
Use only accessible external adjustment points.
Do not disassemble sealed components.
If yes
Continue to Step 5.
If no
If you cannot safely identify the adjustment location:
contact support before continuing
If the issue clears
Monitor the bike during future rides.
If the issue remains
Continue to Step 5.
Step 5 – Adjust Brake Sensor Sensitivity
Using the correct tool:
slightly loosen the adjustment set screw if required
make small adjustments only
avoid over-tightening
Turn the bike on and monitor the display while testing the brake lever.
If yes
If Error 25 disappears:
continue testing carefully
ensure the motor disengages correctly when braking
If no
Continue making small adjustments carefully.
If the issue clears
The brake sensor sensitivity was likely misadjusted.
Monitor the bike during future rides.
If the issue remains
Continue to Step 6.
Step 6 – Recheck Motor and Brake Function
With the bike powered on:
test both brake levers again
confirm the motor disengages while braking
confirm the motor resumes normally after releasing the brake
If yes
If everything operates normally:
continue monitoring the bike
If no
Continue to Step 7.
If the issue clears
The brake sensor adjustment resolved the issue.
If the issue remains
Continue to Step 7.
Step 7 – Contact Support
If the issue remains after adjustment:
stop riding the bike
do not continue adjusting the brake sensor
do not attempt internal electrical repairs
Please contact our support team with the photos/videos listed below so we can review the next step.
The issue may involve:
the brake sensor
brake sensor wiring
brake lever assembly
internal electrical connections
When To Contact Support
Please contact support if:
Error 25 or Error 26 remains
the motor does not disengage correctly while braking
the motor cuts out unexpectedly
visible cable or connector damage is found
the brake lever feels abnormal
the bike has been exposed to impact, crash, transport damage, water exposure, modification, or third-party repair
you are unsure how to safely complete the adjustment
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 or proof of purchase
Aventon model
photo or video of the issue
photo of Error 25 or Error 26 if shown
photo of the brake levers
photo of visible brake sensor wiring
photo of visible connectors if safe
photos of any 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 motor disengages while braking
confirmation of whether the issue happened after impact, water exposure, modification, or third-party repair
confirmation of which troubleshooting steps have already been completed
Important Safety Notes
Do not continue riding if braking behaviour is abnormal.
Do not ride if the motor continues engaging while braking.
Do not open the battery, controller, or sealed electrical components.
Do not force connectors or adjustment screws.
Do not work on wiring while the bike is powered on or connected to the charger.
Contact support if you are unsure about any step.