CarPlay, Android Auto, Wi-Fi and Bluetooth together
The car has one Wi-Fi radio and one Bluetooth radio for many things at once: phone projection, the head unit's internet, the hotspot and more than one device. The head unit follows fixed rules so all of it can live together. Here are the answers to the most common questions.
This page describes the rules the head unit follows. The team is still checking some of them in the car, and anything that needs a newer version says from which version it applies. If something in your car differs from what is written here, tell support (see the last question).
Why does the car's Wi-Fi go away when CarPlay starts and then come back?
The car has a single Wi-Fi radio. While CarPlay or Android Auto uses the car's hotspot, the radio cannot also talk to your home or work network unless it is on the same 5 GHz channel: jumping from one channel to the other cuts the audio and the picture of the projection. In that case the head unit puts the Wi-Fi to silence, on purpose and not forever: it comes back at the first opportunity, when the projection ends, when the hotspot closes or when a saved 5 GHz network shows up on the hotspot's channel. For that, the head unit looks at that one channel only, from time to time, precisely so it does not disturb the projection.
Does the hotspot close by itself?
The car's Android closes the access point after about 10 minutes with no device connected. The head unit reopens it by itself, the normal way, and it never drops the car's Wi-Fi to do so: the two only live together when the Wi-Fi is on a 5 GHz network on the same channel as the hotspot. If the Wi-Fi is on a network that does not share the channel, the hotspot waits. The priority is not to drop your Wi-Fi.
Applies from head unit version 1.3.2.4385.
Where does the head unit's internet come from now?
The «Network & Auto» tab of the head unit app says, in one word, how the internet arrives: through Wi-Fi, through the phone's Bluetooth, or that there is no internet. The order is this: first Wi-Fi (home, work or the Personal Hotspot of the phone whose turn it is); then the Bluetooth of that phone, when it has Personal Hotspot on (iPhone) or Bluetooth tethering (Android). The internet of the car's factory module is not part of this. Bluetooth is requested whenever the Wi-Fi is silent or has no internet, with or without CarPlay running.
Two phones in the car: which one connects?
One at a time. The turn belongs to the last device you chose: by tapping it in the app list, on «Use now», on the projection card or on the phone itself. A device that joins the car on its own does not take the turn. The other paired devices wait: they show on the screen, but they do not connect and are not called. Switching is your decision, and the switch is exclusive: the other session is closed before the chosen one comes in. The turn lasts until you switch or until the device leaves the car.
I turned Bluetooth off: does the head unit turn it back on?
No. The head unit does not turn Bluetooth off on its own to make room for Wi-Fi or projection (the only automatic restart is the last step of the rescue described in the black-screen question). If you turn it off from the car's panel, it respects your choice, even when the head unit app restarts during the same trip. When you turn the car off and on again, things go back to normal: yesterday's choice does not apply to today's car.
Applies from head unit version 1.3.2.4603.
Black screen on CarPlay: what does the head unit do by itself?
First it checks that the session really has no picture, looking at the whole log and the frames drawn, not just one line. Then it climbs a rescue ladder: it asks the adapter to close only the channels of that iPhone and tries again, checking for about 20 seconds. Only if that is not enough does it restart the car's Bluetooth, and that restart exists only as the last step. Restarting Bluetooth drops for a moment whatever was on it, such as internet over Bluetooth; so, after it, the head unit waits for the chosen iPhone to come back before calling another device.
Does Android Auto follow the same rules as CarPlay?
Mostly, yes. Android Auto joins the same turn list as CarPlay, and the choice you make applies to both. CarPlay is never sent to an Android phone. One channel at a time: if CarPlay is connecting, tapping the Android Auto card waits. The difference is the rescue: Android Auto does not use the channel CarPlay uses to talk to the car, so tapping its card never restarts Bluetooth and never touches internet over Bluetooth.
What can I do when projection does not start?
Wait a few seconds: the head unit tries by itself and, if the automatic attempt runs out, it stays quiet and only tries again after a few minutes, unless you ask. Asking is easy: tap the projection card or, on the «Network & Auto» tab, «Use now» on the device you want to use. Also check that the phone's Bluetooth is on and that it is the device whose turn it is. If the screen goes black, the head unit takes care of it, as described above.
What does the head unit deliberately not do?
The head unit was built to never take away from the car what is factory. Without an account with a valid pass, or with the head unit stopped, the car goes back to behaving as it left the factory; our adjustments only act when the head unit turns them on, and the priority of paired devices is put back to normal at start-up. It also does not search for Wi-Fi networks while projection is running (an ordinary search cuts the audio and the picture) and does not pick another device on its own in place of the one you chose.
How do I send support a useful report?
Say what you saw and when: the day and approximate time, whether it was CarPlay or Android Auto, whether the car had just been turned on and, if you know it, the head unit version. Do not send Wi-Fi passwords, device addresses or your phone's name: the head unit does not send them either. If you want support to see the head unit's log, turn on «Allow remote support» in the app; without that switch, support cannot read the log.