First, determine whether the navigator supports SD card. If so, find a multi-function card reader and insert an SD card. Then look at it on the computer, and first determine whether it is an SD card or a car navigator.

By default, the SD card (FAT32) is reformatted, and then an attempt is made to copy it.

The SD card is not clean, and the metal area of the SD card will be stained with dust or oil, resulting in poor contact of the card slot, and sometimes it cannot be read. Try cleaning the metal area of the SD card.

The wire in the slot is rusted. Nowadays, SD cards all support hot plugging, and frequent plugging and unplugging of SD cards will cause excessive bending or rust of card slot lines. Carefully check whether the check card slot line is bent or rusted. If it is bent, take the thread off with a needle; If it is rusty, it can be cleaned.

If the mobile phone navigator can't recognize the SD card, you can try the following methods. Take Kay LiDE navigation as the column:

First of all, Khalid installer will search for map data according to the default storage location of mobile phone system. If it can't find it, it will search according to some built-in absolute paths. If these absolute paths do not include the path of your mobile phone's SD card, then there will be a problem that the mobile phone navigator cannot identify the SD card. So it is very simple, what we need to do is to add the absolute path of your mobile phone SD card in the configuration file of the installation program, so that the software can find the map data smoothly.

Second, modify the APK file of Android. The process is: decompile the original installation package, modify and save, compile, sign and package. You can use the integration tool ApkTool.

3. First, choose to download and install the JAVA running environment according to your computer system, extract the above tools to the ApkTool folder, copy the apk file of Kailide that needs to be modified to the apktool folder, and rename it to 123.apk, then run the APKtool.cmd file and select 1 to decompile. When finished, a new apk folder will be generated. For Khalid version 4.0, you can find the "smali\cld\navi\mainframe" folder, open the Navipath.smali file in it with notepad, and find the first path statement.

Fourth, just overwrite the path of your mobile phone SD card and save this file. As shown in the figure (Note: the modified path in the figure is Redmi 1s telecom mobile phone, and the SD card paths of different mobile phones are different):

For Khalid v5.0, the AppConfig file in smali\cld\custom is modified in a similar way.

5. How to determine the absolute path of your mobile phone SD card? If you have installed Wei Yun, it's very simple: Open Wei Yun and select Upload File, and the selection path will appear, one is the built-in storage path and the other is the external SD card storage path. The following example is Redmi 1 mobile version, and /storage/sdcard0 is the absolute path of SD card. The SD card path of Redmi Telecom 1s is: /storage/sd card 1.

6. Run APKTool.cmd again, and select 3 to compile the modified file and sign it as a new apk. When finished, a new build folder will be created under the apk folder, which contains compiled and signed APK files. This is the kailide navigation installation package for your mobile phone. After being installed on the mobile phone, you can read the map data stored on the SD card normally.

Summary: Although the above example is only one type of navigation, it can be applied to other types. In addition, it is necessary to rule out whether there is a problem with the SD card itself in advance, and then consider the problem that navigation cannot recognize it. In any case, we should try to exclude more.