The Autel EVO II Troubleshooting Guide

DroneLogix has hundreds of hours of logged flight time flying the Autel EVO II series platforms, both Pro and Enterprise models, and both V2 and V3 models.  Below are insights that we have learned from flying and maintaining these aircraft.

Additional Resources:

EVO II Main Downloads Page

EVO II Pro Series Downloads

EVO II Enterprise Series Downloads

EVO II Enterprise RTK Series Downloads

EVO II Enterprise Dual (Thermal) Series Downloads

EVO MAX Series Downloads

---

Explorer App Message: "failed to obtain device list" message

We noticed this message on a couple of V3 devices in our fleet when using the 7.9" Smart Controller while attempting to update the device name. This appears to be an issue for aircraft running the Autel Explorer app version 3.1.49.

Resolution: 

The Smart Controller should be connected to its aircraft during this process, so power on both devices. On the Smart Controller, go to Settings (swipe up from the bottom of the screen and press the circle), go to Apps & notifications and then select the Autel Explorer app. On the App Info page select the three dots in the upper right corner and select uninstall updates. Click on OK when the dialog opens that asks you to "Replace this app with factory version? All data will be removed." Go back to the Autel Explorer app click on the Profile icon in the upper right corner of the main screen and log in to your Autel account. After login, you should be able to navigate open My Devices and see your aircraft serial number and bound email information. You can change the device name by clicking on the edit icon next to the device name at the top of the page.  After confirming access to your aircraft in My Devices, click the Camera button on the main screen and navigate to the settings area (gear icon in upper right of screen) and select the General settings page . Click on Software Update and select APP and update the software to the latest version. Following the update, reboot both the aircraft and remote controller and confirm you can access the aircraft data in My Devices.

NOTE: If you previously installed the firmware that is associated with the upgraded Autel Explorer app version (in this example the APP version is V3.1.49), you will not need to reinstall the firmware on the aircraft.

---

Gimbal Automatic Calibration Fails

This particular problem was present on earlier firmware versions (Year 2022 - Version 2.3.23 and earlier) of the EVO II Enterprise V2 6K model, then was introduced on the EVO II Pro around July 2022 (version 2.7.35). We experienced this using the 7.9" Smart Controller and the 6K gimbal, so it may not be an issue with iOS or mobile Android versions of the Explorer app or other gimbals.

Resolution: 

This bug has been rectified by recent (Year 2023) firmware updates, so update to the latest firmware to fix the issue. If you do not wish to update, the workaround is to remove any third-party filters (i.e. Freewell filter) on the camera lens prior to performing a gimbal automatic calibration.

---

Explorer App Message: “Your remaining server space is less than 28.0MB  Click Continue, your earliest records will be deleted.”

This occurs when your flight record data volume has outgrown the alloted Autel cloud storage associated with your Autel account login credentials and you attempt to sync your flight records from your device to the cloud. Clicking on Continue causes the sync process to fail. Clicking on Cancel cancels the sync process, as expected. When you experience this condition, your flight records stored on the remote controller will not sync to the Autel cloud and therefore your third-party aircraft or flight management software (e.g. Airdata, Dronelogbook, etc.) will also fail to sync and load recent flight data. Additionally, multiple attempts to run the sync process during the same session returns errors with the server space number bouncing around from 28.0MB to 20.0MB. The number is different almost every time and it goes up and down during this session.

NOTE: This condition has nothing to do with local remote controller storage space, so don't waste time trying to analyze local storage.

Resolution: 

Contact Autel Support at support@autelrobotics.com and request that they increase your alloted cloud storage space for flight records for your account. You will need to supply them with the email address you use to login to your Autel account. They should make the change within a day or two, usually the same day. In the interim, DO NOT “Clear Local” data since the locally stored flight records are not yet synced to Autel's cloud storage.

---

Smart Controller V3 Fails to Pair with the Evo II Pro V3

This occurs when the Smart Controller fails to upgrade properly, even though the firmware upgrade process reports success.  This condition can occur for all editions of the EVO II, both Pro and Enterprise. Essentially, the Smart Controller Remote Control firmware gets stuck on an earlier version (e.g. V6.0.2.0) instead of upgrading to the newer version (e.g. V6.0.2.6) during the upgrade process. There is no indication of an error during the upgrade process. If the remote controller's firmware version does not upgrade properly, it will be unable to communicate with the V3 EVO II Pro (or Enterprise) that is running a newer or different version of firmware. Review the Firmware Version Table information found on the Autel Robotics downloads page to understand and compare version numbers found in the table with those shown on the Remote Controller. In our case, we were upgrading from V1.0.10 to the latest V1.1.9 (EVO II V3) firmware during June 2023. The Smart Controller we upgraded over-the-air (OTA) to V1.1.9 upon receipt, but the Remote Control portion of the firmware package did not upgrade properly. Consequently, we could not bind the Remote Controller with the aircraft, even though the two devices could communicate together out of the box.

Resolution: 

Short Instructions: Downgrading the firmware, pairing/binding, then upgrading to the latest firmware resolved the issue.

Detailed Instructions: 

NOTE: You may need to engage Autel Support at support@autelrobotics.com for assistance with securing a copy of the previous firmware version in order to complete the steps below.  They closely manage access to firmware, so we recommend that you share you are unable to bind your aircraft with its remote controller after performing a firmware upgrade. As part of our firm's best practices, we maintain a copy of each firmware version and details when released.

We will be downgrading the aircraft firmware to the earlier version (in our case, V1.0.10) using the correct version file supplied by Autel or that you may have saved from earlier updates. Once your aircraft is downgraded, we will then do the pairing mode on the aircraft and smart controller.  Once they pair, you should then receive an over-the-air (OTA) firmware update notification to upgrade to the newer firmware version (in our case, V1.1.9).

In our case, we were attempting to pair to a Smart Controller 7.9" device, not the Smart Controller SE device that shipped with the aircraft. For this process, we did not utilize the SE controller at all. If you are in a similar situation, please leave the SE controller off. 

Here are detailed instructions for a manual update:

BEFORE YOU BEGIN: Make sure that both devices have at least 80% battery power before performing the update process to minimize this risk.

1. Download the firmware zip file and copy it to the root folder (no sub-folders) of a Micro-SD card. DO NOT unzip it.
2. Power on the aircraft and the Remote Controller. They will not be connected in this particular case.
3. Insert the SD card into the aircraft, and the firmware update process will start automatically. You will see the aircraft LED indicators rapidly flash. Nothing will indicate on the Remote Controller since the two devices are not connected.
4. Wait about 30+ minutes, and you will see the aircraft LED indicators become solid, indicating the firmware update has been completed.
5. After the aircraft update is completed, power cycle the aircraft and Remote Controller. We will do this step whether or not the update passes or fails. If the update fails and the remote control refuses to connect to the aircraft after following these steps, contact Autel Support, because there will be a new set of instructions for you to follow if this happens. (It is not typical that the update fails and then doesn't connect.)
6. If the aircraft and remote controller indicate they are connected, you should receive an over-the-air (OTA) firmware update notification to upgrade to the newer version. Perform the update, power cycle the aircraft and Remote Controller and confirm they are able to connect and communicate.

---

What About Non-Autel, Aftermarket Batteries?

We are not aware of any non-Autel, aftermarket batteries, but should you buy one, never use a non-Autel battery for drone flights.  They are fine for ground activities such as gimbal calibrations, IMU calibrations, firmware updates, or powering ancillary devices or charging your controller in the field when using a special cable designed for this purpose.  For flights, only use an original equipment, Autel manufactured Intelligent Flight Battery, part number AR-EV2BT.  Flights made with a non-Autel battery that result in a crash will void the aircraft warranty, including coverage under Autel Care Refresh.

Fly safe!