Aventon Mid Drive – W122 / W123 SIM Card Not Detected / Cellular Hardware Module Disconnect TroubleshootingUpdated 2 days ago
This article explains how to troubleshoot the W122 and W123 SIM Card Not Detected / Cellular Hardware Module Disconnect errors on Aventon mid drive eBikes with an ACU/ECU (Aventon Control Unit).
Use this article if your bike:
shows a W122 or W123 error code
has cellular connection issues
cannot connect correctly to app-based cellular features
displays a SIM card or cellular hardware warning
If you are unsure about any step or anything looks unsafe, stop and contact support before continuing.
Before You Start
Please prepare the following before troubleshooting:
your order number
your Aventon model
a photo or video of the W122 or W123 error code
screenshots or video showing the issue
when the issue first appeared
confirmation of whether the bike powers on
confirmation of whether the display turns on
confirmation of whether the bike connects to the Aventon app
confirmation of whether the issue started after transport, storage, software update, water exposure, impact, modification, or third-party repair
photos of any visible damage
Safety Warnings
Do not continue riding if the bike has a persistent error code.
Do not continue riding if there is visible damage, overheating, smoke, or a burning smell.
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 about any step.
What This Error Means
The W122 and W123 errors indicate that the bike cannot detect the SIM card or that the cellular hardware module is disconnected.
This may happen because:
there may be a software issue in the current ECU version
the SIM card inside the cellular module may be damaged
the cellular module may be damaged
Possible Causes
Possible causes include:
ECU software issue
damaged SIM card inside the cellular module
damaged cellular module
Troubleshooting Steps
Step 1 – Restart the Bike
Power off the bike completely.
Wait approximately 10 seconds.
Then power the bike back on.
Check whether the W122 or W123 error is still displayed.
If yes
If the W122 or W123 error remains after restarting:
continue to Step 2
If no
If the W122 or W123 error clears after restarting:
continue monitoring the bike during normal use
If the issue clears
The issue may have been caused by a temporary communication or startup issue.
Continue monitoring the bike.
If the issue remains
Continue to Step 2.
Step 2 – Update the ECU Software
Open the Aventon app and check for available ECU software updates.
If updates are available:
update the ECU software to the latest version using the Aventon app
keep the bike powered on during the update process
do not disconnect the app during updates
After the update:
restart the bike
reconnect the bike to the Aventon app
check whether the W122 or W123 error remains
If yes
If the W122 or W123 error clears after the update:
continue monitoring the bike during normal use
If no
If the W122 or W123 error remains after updating:
continue to Step 3
If the issue clears
The issue was likely related to ECU software or communication.
Continue monitoring the bike.
If the issue remains
Continue to Step 3.
Step 3 – Check Whether the Issue Persists
After restarting and updating the ECU software, check whether the W122 or W123 error still appears.
Check whether:
the bike connects correctly to the Aventon app
cellular features function correctly
the error code remains active
If yes
If the W122 or W123 error remains:
please contact our support team with the photos and videos listed below so we can review the next step
If no
If the W122 or W123 error no longer appears:
continue monitoring the bike during normal riding and app use
If the issue clears
The issue may have been caused by temporary software or communication interruption.
Continue monitoring the bike.
If the issue remains
Please contact support.
When To Contact Support
Please contact support if:
the W122 or W123 error remains after completing the steps above
the bike cannot connect correctly to app or cellular features
the bike does not power on
the display does not turn on
there is visible damage
the issue appears to involve the ECU, cellular module, SIM card, connector, cable, controller, or internal wiring
the bike has been exposed to water, crash damage, impact, transport damage, modification, or third-party repair
you are unsure how to safely complete any step
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 the following:
your order number
your Aventon model
a photo or video of the W122 or W123 error code
screenshots of the Aventon app, if relevant
a photo of the display
photos of any visible damage
confirmation of whether the bike powers on
confirmation of whether the display turns on
confirmation of whether the bike connects to the Aventon app
confirmation of whether cellular features function correctly
confirmation of whether ECU software updates were attempted
confirmation of whether the issue started after transport, storage, software update, water exposure, impact, modification, or third-party repair
confirmation of which troubleshooting steps you have already completed
Important Safety Notes
Do not continue riding if the W122 or W123 error remains.
Do not ride the bike if there is visible damage, overheating, smoke, a burning smell, or water exposure.
Do not open the battery, controller, ECU, cellular module, SIM card compartment, or sealed electrical components.
Do not force connectors or electrical components.
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.