Upgrade reading guide
How to upgrade UX999Ultra firmware normally 1. Obtain the firmware upgrade package, two files named "APM1688.zip" and "applepie_update.json". 2. Please prepare a TF card, and put "APM1688.zip" and "applepie_update.json" directly into the TF card (directly placed in the root directory, no need to create any folder, and no need to unzip the zip file). 2. At this time, please insert this TF card for upgrade. The file system detects that there are upgrade files in the TF card, and a pop-up window will ask whether to upgrade. Immediately (within 20 seconds) click the "Cancel" button to cancel the upgrade operation. Please pull out the upgrade card; if you click "OK" or do nothing (wait for a timeout of 20 seconds), the system will enter the upgrade operation. 3. First, copy the upgrade file to the internal storage space. The copy progress will be from 0% to 100%. After the copy is completed, the system will pop up a pop-up prompt to automatically restart. 4. After the system restarts, you can pull out the TF card, and the rest of the steps will be completed automatically. You just have to wait to get to the main screen display of the UX999 Ultra again. The entire upgrade process takes about 15 minutes. Note: It is better not to cut off the power during the upgrade process, and do not pull out the TF card during the process of copying the upgrade files to the internal memory. Of course, if the above situation occurs, the UX999 Ultra will not be damaged, and it will work normally after restarting. It's just that your upgrade process has been canceled this time, and the normal upgrade cannot be completed.
How to upgrade the firmware without seeing the device screen (blind upgrade)

Get the firmware upgrade package, two files named "APM1688.zip" and "applepie_update.json". Please prepare a TF card, and put "APM1688.zip" and "applepie_update,json" directly into the TF card (directly placed in the root directory, no need to create any folder, and no need to unzip the zip file) You can use the CarPlay USB port on the car to power up the box, or you can use a mobile phone charger with 5V/2A DC output from the USB port to power up the box. After the box is powered on, please wait for 2 minutes to ensure that the red power indicator on the box is always on, and the blue working status indicator flashes once every second. At this point, please insert the upgrade TF card, about 3 minutes, when the blue LED is always on and the red LED is flashing, you can pull out the upgrade card. Wait another 10 minutes or so, when the red LED is always on and the blue LED flashes once every second, the upgrade process is complete. The entire upgrade process takes about 15 minutes. Note: It is better not to cut off the power during the upgrade process, and do not pull out the TF card during the process of copying the upgrade files to the internal memory. Of course, if the above situation occurs, the UX999 Ultra will not be damaged, and it will work normally after restarting. It's just that your upgrade process has been canceled this time, and the normal upgrade cannot be completed.
Upgrade Video Guide
2022-10-20
2022-10-18
https://drive.google.com/drive/folders/1K0th_HHblzqnETiu_vJ8-HfBfewIk2Yf?usp=sharing&_saltLurl2022-10-20

Solved the video display problem of reverse switching on the latest Mercedes-Benz C-Class. Fixed a video display issue with the latest Mercedes-Benz S-Class.