Phone not connecting to carplay via cable

If your iPhone isn't detected by CarPlay, make sure that CarPlay isn't restricted. Go to Settings > Screen Time > Content & Privacy Restrictions, tap Allowed Apps and make sure that CarPlay is enabled. ... Then set up CarPlay again. Make sure that your CarPlay stereo is using the latest firmware from the car manufacturer.

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So my neighbor just got a 2021 GLC300 and my iPhone with my cables work rock-solid in his car. There is also a FW difference between the two cars. Now the dealership says they will do a FW update to see if that helps, “and possibly replace the jumper cable between the center console and the head-unit”. Here are pictures of the error I get and the FW’s from both cars (2020 vs 2021).

So after being made fun of by the MB dealership service advisor (here in our town just south Portland) after i told him that my neighbor who is an engineer at Daimler (trucks) thought it could be the cable between the center console and the head unit (the advisor yelled “oh an engineer” sarcastically), he had to call me an hour later to say “you were right, its a bad cable and we need to order the part.”

[Edited by Moderator]

I have a 2020 GLC-300 with the latest FW updates. CarPlay will fail just about every time unless I let the system fully boot and don't put the car in reverse, and even then it's hit-or-miss. Once I am driving, plugging it in then will launch CarPlay successfully just about every time. I have an iPhone 12 with v14.5 but it also had the same issue with the previous SW version. MB dealership says it's an Apple issue... I have tried all combinations of cables and am currently using the MB USB-A to C adapter and an Apple USB-A to Lightning.

My son has a 2018 Ford Focus SE, and CarPlay works with my phone every time.

I am having the same problem on a 2021 Hyundai Sonata. USB will not connect CarPlay to my IPHONE even though it charges and works for a memory stick playing music. New Apple cable. The same phone worked on a 2017 Hyundai Sonata.