Android Auto Not Working

[olds]

HU has AA.
AA app is installed on my S9+ running Pie.
Tried 3 cables.
AA runs on phone.
HU sees the phone connected via USB.
Phone also connected to HU via bluetooth.
AA does not run on HU
If I use the phone in AA, everything goes through the phone, not the HU.

Any ideas? TIA

 

[Zaap]

Try this. Open Android Auto on your phone. Go to settings. Find connected cars.

Check nothing is listed especially under rejected. (Unless of course you use AA in another vehicle)

Untick the button to add new cars to AA.

Sometimes that can mess with a head unit because it expects to connect and setup in a factory unit. Hopefully helps.

If not...check for a software/firmware update for both car and head unit.

 

[olds]

Thanks. Tried that, no joy.
I was messing with the selections for when you plug the USB cable into the phone. It's now working after selecting MIDI. I tried USB Tethering and it didn't work but for some reason does with MIDI.