Android Auto 17.4 on Tesla: turn on the head unit server (video guide)
If your Tesla screen has been stuck on step 2, “Socket connected, waiting for stream” since a recent update, and the Android Auto welcome popup never shows up on your phone, you are not doing anything wrong. Google changed how Android Auto starts a wireless session in version 17.4, and every phone that receives the update needs one setting that did not exist before. The video above shows the whole thing on a real phone; the text below explains what changed, why, and how to get past each of the three traps that catch most people.
What changed in Android Auto 17.4
Until Android Auto 17.3, a third-party head unit like TaaDa could ask the phone to start a wireless projection session on its own. TaaDa did exactly that: you pressed Start, Android Auto woke up, showed its welcome popup, you tapped Continue and the Tesla browser received the video stream a few seconds later.
Android Auto 17.4, rolled out to everyone in August 2026 and followed by 17.5, removed that automatic start. The phone no longer answers a projection request coming from an app. The only way left to open a session over Wi-Fi is the head unit server that Android Auto has always carried for developers: a small service inside Android Auto that waits for a head unit to connect to it. It is switched off by default, hidden behind Android Auto’s developer settings, and nothing but the Android Auto interface can switch it on.
TaaDa 2.7 and later detects an Android Auto 17.4 or newer and changes side: instead of asking the phone to start, it waits for the head unit server and connects to it. From then on the session works exactly as before, same video, same touch, same audio. The one thing that changed for you is that the server has to be running.
How to tell this is your case
- The Tesla screen reaches step 2 and stays there, whatever you do with the cache, the battery settings or a phone restart.
- No Android Auto popup appears on the phone when you press Start in TaaDa.
- On the phone, TaaDa shows a screen titled “One last setting on your phone” with a blue button, and a notification saying that TaaDa needs you for ten seconds.
- In the Android Auto settings, the Version line at the bottom starts with 17.4, 17.5 or higher.
If you see the older troubleshooting advice on the Tesla screen (battery optimization, clear the cache, restart the phone), ignore it for this case. It cannot start a server that is off.
Before you start: forget the old car profile
If TaaDa already worked on this phone before the update, Android Auto still holds a vehicle profile from the old way of connecting. It does no harm most of the time, but when the welcome popup refuses to show up at the end of the procedure, that stale profile is the usual reason. Clearing it takes ten seconds (the video skips this step, it is only needed in that case):
- Open the Android Auto settings on the phone (the next section explains where they are).
- Tap Previously connected cars.
- Tap the three dots at the top right, then Forget all cars.
- Go back to the Android Auto settings screen.
Skip this if TaaDa has never connected on this phone.
Step by step: turn on the head unit server
- On your phone, open Settings, type Android Auto in the search box at the top and open the result. This route works on every brand. On Samsung the same screen lives under Settings, Connected devices, Android Auto; on a Pixel under Settings, Connected devices, Connection preferences, Android Auto.
- Scroll to the very bottom of the Android Auto settings. The last line is Version (some phones call it Version and permission info).
- Tap Version ten times in a row, about one tap per second. A message confirms that developer settings are now enabled.
- Tap the three dots at the top right of the same screen, then Start head unit server. A permanent notification appears in the status bar: the server is running.
- Open TaaDa and tap Start. TaaDa finds the server within a few seconds.
- Android Auto now shows its welcome screen on the phone. Tap Continue, at the bottom right. Never tap Exit.
- Look at the Tesla screen: step 3, the stream starts.
That is the entire procedure. Nothing to type, nothing to install, and the developer mode you just enabled has no other effect on the phone.
The three traps
The first tap does nothing. The first tap on Version only unfolds the line to display the full version number. Most people read that as a failure, stop, and conclude the trick does not work. Keep tapping: the count starts there and the confirmation message arrives around the tenth tap.
The wrong Version line. The ten taps only work on the Android Auto settings screen, the one with Previously connected cars at the top. The Play Store page for Android Auto also shows a version number, and so does the system App info page that some phones open when you tap Android Auto in the app list. Tapping those does nothing. If the screen you reached has no Previously connected cars line, go back to Settings and use the search box.
Exit instead of Continue. The welcome popup that Android Auto shows after you press Start looks like an intrusive notification, and the reflex is to close it with the Exit button at the top. Exit tells Android Auto that this car is refused, and the popup will not come back until the profile is forgotten. Tap Continue, at the bottom right. If you tapped Exit by mistake, forget all cars as described above and press Start again.
After a phone restart
Developer mode survives restarts, the server does not. Every time the phone reboots, or after some system updates, the head unit server is off again and TaaDa goes back to waiting on step 2. The fix is three taps: Android Auto settings, three dots, Start head unit server. No profile reset, no popup this time, since the car is already known. TaaDa shows a shorter reminder screen on the phone in that situation, with the same blue button.
If you restart your phone often, it is worth keeping Android Auto in the recent apps or pinning the settings screen as a shortcut on the home screen, depending on what your launcher offers.
Where the Android Auto settings live, by brand
- Samsung (One UI): Settings, Connected devices, Android Auto.
- Google Pixel and stock Android: Settings, Connected devices, Connection preferences, Android Auto.
- Xiaomi, Redmi, POCO (HyperOS): open the Android Auto app from the app list, then the Additional settings button.
- Huawei (EMUI): the Android Auto app opens on an intermediate screen; the gear at the top right leads to the settings.
- Any brand: Settings, search box, type Android Auto. This is the route used in the video and on the Tesla screen because it never fails.
Why TaaDa cannot flip the switch for you
The head unit server is a service that Google does not export: no application can start it, only Android Auto’s own interface. Automating it would require a rooted phone, or an accessibility service that watches the screen and taps for you, which Google rejects on the Play Store for anything that is not a real accessibility need, with a suspension risk for the whole app. That is why TaaDa guides rather than acts: it recognises Android Auto 17.4, keeps the session alive while you tap, shows the steps on both screens, and connects by itself the moment the server answers.
Quick checklist
- Android Auto version 17.4 or higher on the phone.
- TaaDa updated from the Play Store.
- Old car forgotten if TaaDa worked on this phone before.
- Version tapped ten times on the Android Auto settings screen, confirmation message seen.
- Three dots, Start head unit server, notification visible.
- TaaDa Start, then Continue on the welcome popup.
- After every phone restart: three dots, Start head unit server.