No idea which forum to post in but here seems as good a bet as any!

I bought a wireless CarPlay adapter from a fellow GZer recently - but getting it running is a challenge. It's a CoralVision CarPlay Wireless A unit, they seem to be knocked out under various brand names from the same Taiwanese factory. Just to be clear - no problem at all with the seller, it worked fine for his parents last year but I knew he hadn't tried it out (he was entirely honest about it). He has offered to refund me but that's not required. Kudos to the seller for the offer though.

The issue I gather is since iOS 17.2 the firmware on the device needs updating for wireless CarPlay. There are instructions for how to do this for some other models e.g. here https://carplay.tw/blogs/firmware-update

I have purchased a TF card and with an afternoon of mild swearing, a couple of card readers, an SD adapter, and endless dithering have managed to get the updated firmware disk image on the TF card, which is in the head unit.

However, I can't persuade the unit to boot from it and there's no way I can find to force it to update the firmware. I have tried rebooting the device with the TF card in. I have even guessed the PIN for the settings but there's no firmware option there.

I can still go retro and use it as a wired CarPlay unit - which is fine (and of course this charges the phone via USB at the same time, so probably best overall). But for shorter trips there's some convenience to wireless CarPlay, which would be nice to explore.

Does anyone have any insights as to how to update the firmware?

Many thanks in advance

b