If the dongle's light shows red but can't connect to the dongle, you might try the below methods to solve the problems:
1. Confirm whether your vehicle model and year are in our compatible list (the compatible vehicle list is at the bottom of the product page)
First of all, we need to confirm whether your vehicle is compatible with the Carlinkit 3.0/ 4.0. The car models in the compatible list are the results obtained by engineers through long-term experiments and proofreading. Please do not take the risk to buy a dongle that does not on the adaptation list, so as to cause unnecessary trouble.
Carlinkit 3.0/ 4.0 compatible list: https://autokitcarplay.com/blogs/autokit-blogs/product-u2w-plus
If you are not sure if your vehicle is compatible with our product, please feel free to contact us before you make the purchase decision.
2. Please change a new high-quality cable to connect the dongle with your vehicle.
When it has been confirmed that your vehicle model and year are compatible with our products, the next step is to rule out whether there is a problem with the data cable connecting the product and the car. We recommend you replace a high-quality data cable and then try to reconnect the car. Sometimes it can be used normally after you change a new cable.
3. Please switch the Sync Mode to Compatible mode.
After you change a new cable for the dongle, we need to rule out whether your dongle is in a compatible state.
Below are the operation steps:
a. Log in to the upgrade interface.
After the product is connected to the car successfully, please scan the QR code in the product manual with your mobile phone or input 192.168.50.2 in the mobile browser to log in to the product upgrade interface.
b. Log in to the product setting interface.
At the bottom of the upgrade interface, there is a blue "Check for updates" button and a white Settings logo, please click the "Settings" logo to log in to the product setting interface.
c. Change the Sync Mode from Normal to Compatible mode.
4. Restart your phone & car
After replacing the data cable and changing to the compatibility mode, please restart the phone and car to ensure that the operation has been saved.