So I am trying to get Android Auto working but its been pain so far.
Currently trying to get it working in the owner profile first, but with the hope of getting it running in a secondary or even secondary profile private space later on.

All apps are up to date (release builds). AA version 15.9.655114-release. Tried with no secondary profile started after full phone restart. Orbot VPN enabled. Most apps disabled in owner profile; as one does.

I pretty much set it up as described at https://grapheneos.org/usage#android-auto
Tried to reduce as much friction as possible so enable as much as possible. So gave Android Auto all app permissions, enabled wireless and wired permissions, gave full notification access, always start AA, even limited apps to NewPipe (to test), SMS and phone (not sure if that helps). In the developer options I also set the USB-C setting to always on and default settings to always use file transfer. I have not enabled apps such as Google maps, no speech recognition nor voice commands or the Google app (assuming these are not required and only add additional capability).

No matter what I did so far, the issue has remained with the exact same behavior. It usually tries to connect, phone does a pling sound but after 1-2s it instantly disconnects. I dont manage to select anything (e.g. change USB options) before that happens. Infotainment error modal says that the connection failed. Oddly enough there is a notification by Android Auto that says a connection was established, but that seems to not be correct.

Trying with short USC-C cable (tried two, including the official Pixel 10 Pro one, both connect AA when trying with my old Samsung A52S). Connecting AA via bluetooth also fails. Although I managed to have it play music and take calls over speakers, but I believe that to be base bluetooth functionality and not AA functionality, correct?

Hope someone has had a similar issue and was able to resolve it. Or if this is an unresolved bug.

I got me the AA logs and there are a few error logs. Seems it might fail at the handshake? Here are a select few error lines that seem relevant:

java.io.InterruptedIOException: read interrupted by close() on another thread
IO exception, dataReceived=true, isWireless=false
java.io.IOException: read failed: EIO (I/O error)
Caused by: android.system.ErrnoException: read failed: EIO (I/O error)
FRAMER_READ_IO_EXCEPTION
PROTOCOL_IO_ERROR(3)
READER_CLOSE(52)

More sections, I can provide the full log if required:

[...]
--------- switch to events
02-22 21:13:24.627  4888  4888 I wm_on_create_called: [Token=90052231,Component Name=com.google.android.apps.auto.carservice.gmscorecompat.FirstActivityImpl,Reason=performCreate,time=45ms]
02-22 21:13:24.786  6544  6544 I wm_on_restart_called: [Token=52506706,Component Name=com.google.android.apps.auto.components.settings.connectacar.ConnectACarActivity,Reason=performRestart,time=0ms]
02-22 21:13:24.787  6544  6544 I wm_on_start_called: [Token=52506706,Component Name=com.google.android.apps.auto.components.settings.connectacar.ConnectACarActivity,Reason=handleStartActivity,time=0ms]
02-22 21:13:24.810  6544  6544 I wm_on_resume_called: [Token=52506706,Component Name=com.google.android.apps.auto.components.settings.connectacar.ConnectACarActivity,Reason=RESUME_ACTIVITY,time=0ms]
02-22 21:13:24.810  6544  6544 I wm_on_top_resumed_gained_called: [Token=52506706,Component Name=com.google.android.apps.auto.components.settings.connectacar.ConnectACarActivity,Reason=topWhenResuming]
02-22 21:13:24.826  6544  6544 I viewroot_draw_event: [window=VRI[ConnectACarActivity],event=Start draw after previous draw not visible]
02-22 21:13:24.831  6544  6544 I viewroot_draw_event: [window=VRI[ConnectACarActivity],event=reportDrawFinished seqId=0]
--------- beginning of main
02-22 21:13:24.874  4888  6592 I CAR.GAL.SECURITY.LITE: Successfully initialized SSL context for protocol: TLSv1.2 using provider: GmsCore_OpenSSL
02-22 21:13:24.877  4888  6592 I CAR.GAL.GAL.LITE: Creating per-channel priority writer thread.
02-22 21:13:24.878  4888  6592 I CAR.GAL.GAL.LITE: Creating PerChannelQueue for channel 0
02-22 21:13:24.879  4888  6592 I GH.CAR.ProxyEP.LITE: Proxy created for channel 0
02-22 21:13:24.880  4888  4888 I DynamiteModule: Considering local module com.google.android.gms.googlecertificates:0 and remote module com.google.android.gms.googlecertificates:7
02-22 21:13:24.880  4888  4888 I DynamiteModule: Selected remote version of com.google.android.gms.googlecertificates, version >= 7
02-22 21:13:24.880  4888  4888 V DynamiteModule: Dynamite loader version >= 2, using loadModule2NoCrashUtils
02-22 21:13:24.914  4888  4888 I CAR.STARTUP.LITE: Handoff status true
02-22 21:13:24.915  4888  7220 I CAR.SETUP.SERVICE.LITE: handoff initiated: true
02-22 21:13:24.919  6273  6835 I GH.ConnLoggerV2: Session 9a974462-f24f-4485-bbd7-39a05e302377, event 37, detail OptionalInt.empty, CONNECTION_HANDOFF_COMPLETE, at 241356 
02-22 21:13:24.922  6273  6835 I GH.ConnLoggerV2: Session 9a974462-f24f-4485-bbd7-39a05e302377, event 38, detail OptionalInt.empty, FRAMER_STARTED, at 241356 
02-22 21:13:26.610  4888  6591 I CAR.SETUP.LITE: Closing 1 FDs due to USB disconnect (connected=true, configured=false, accessory=true)
02-22 21:13:26.610  6273  6835 I GH.ConnLoggerV2: Session 9a974462-f24f-4485-bbd7-39a05e302377, event 39, detail OptionalInt.empty, GH_USB_CONNECTED, at 243049 
02-22 21:13:26.617  6273  6835 I GH.ConnLoggerV2: Session 9a974462-f24f-4485-bbd7-39a05e302377, event 40, detail OptionalInt.empty, USB_FD_CLOSED, at 243051 
02-22 21:13:26.628  4888  7239 W CAR.GAL.GAL.LITE: IO exception, dataReceived=false, isWireless=false
02-22 21:13:26.628  4888  7239 W CAR.GAL.GAL.LITE: java.io.InterruptedIOException: read interrupted by close() on another thread
02-22 21:13:26.628  4888  7239 W CAR.GAL.GAL.LITE: 	at libcore.io.Linux.readBytes(Native Method)
02-22 21:13:26.628  4888  7239 W CAR.GAL.GAL.LITE: 	at libcore.io.Linux.read(Linux.java:231)
02-22 21:13:26.628  4888  7239 W CAR.GAL.GAL.LITE: 	at libcore.io.ForwardingOs.read(ForwardingOs.java:624)
02-22 21:13:26.628  4888  7239 W CAR.GAL.GAL.LITE: 	at libcore.io.BlockGuardOs.read(BlockGuardOs.java:325)
02-22 21:13:26.628  4888  7239 W CAR.GAL.GAL.LITE: 	at libcore.io.ForwardingOs.read(ForwardingOs.java:624)
02-22 21:13:26.628  4888  7239 W CAR.GAL.GAL.LITE: 	at libcore.io.IoBridge.read(IoBridge.java:621)
02-22 21:13:26.628  4888  7239 W CAR.GAL.GAL.LITE: 	at java.io.FileInputStream.read(FileInputStream.java:353)
02-22 21:13:26.628  4888  7239 W CAR.GAL.GAL.LITE: 	at hsb.run(SourceFile:108)
02-22 21:13:26.640  6273  6835 I GH.ConnLoggerV2: Session 9a974462-f24f-4485-bbd7-39a05e302377, event 41, detail OptionalInt.empty, FRAMER_READ_IO_EXCEPTION_WITH_NO_DATA_RECEIVED, at 243069 
02-22 21:13:26.644  4888  7220 E CAR.SETUP.LITE: ProjectionErrorCode = PROTOCOL_IO_ERROR(3), ProjectionErrorDetail = READER_CLOSE(52), io error

[...]

02-22 21:13:34.851  4888  7235 E GoogleApiManager: Failed to get service from broker. 
02-22 21:13:34.851  4888  7235 E GoogleApiManager: java.lang.SecurityException: Unknown calling package name 'com.google.android.gms'.
02-22 21:13:34.851  4888  7235 E GoogleApiManager: 	at android.os.Parcel.createExceptionOrNull(Parcel.java:3382)
02-22 21:13:34.851  4888  7235 E GoogleApiManager: 	at android.os.Parcel.createException(Parcel.java:3366)
02-22 21:13:34.851  4888  7235 E GoogleApiManager: 	at android.os.Parcel.readException(Parcel.java:3342)
02-22 21:13:34.851  4888  7235 E GoogleApiManager: 	at android.os.Parcel.readException(Parcel.java:3284)
02-22 21:13:34.851  4888  7235 E GoogleApiManager: 	at bdks.a(:com.google.android.gms@255034035@25.50.34 (260400-855735097):36)
02-22 21:13:34.851  4888  7235 E GoogleApiManager: 	at bdit.z(:com.google.android.gms@255034035@25.50.34 (260400-855735097):143)
02-22 21:13:34.851  4888  7235 E GoogleApiManager: 	at bcow.run(:com.google.android.gms@255034035@25.50.34 (260400-855735097):42)
02-22 21:13:34.851  4888  7235 E GoogleApiManager: 	at android.os.Handler.handleCallback(Handler.java:1070)
02-22 21:13:34.851  4888  7235 E GoogleApiManager: 	at android.os.Handler.dispatchMessage(Handler.java:125)
02-22 21:13:34.851  4888  7235 E GoogleApiManager: 	at cqvy.mv(:com.google.android.gms@255034035@25.50.34 (260400-855735097):1)
02-22 21:13:34.851  4888  7235 E GoogleApiManager: 	at cqvy.dispatchMessage(:com.google.android.gms@255034035@25.50.34 (260400-855735097):5)
02-22 21:13:34.851  4888  7235 E GoogleApiManager: 	at android.os.Looper.dispatchMessage(Looper.java:333)
02-22 21:13:34.851  4888  7235 E GoogleApiManager: 	at android.os.Looper.loopOnce(Looper.java:263)
02-22 21:13:34.851  4888  7235 E GoogleApiManager: 	at android.os.Looper.loop(Looper.java:367)
02-22 21:13:34.851  4888  7235 E GoogleApiManager: 	at android.os.HandlerThread.run(HandlerThread.java:139)
02-22 21:13:34.851  4888  7235 W GoogleApiManager: Not showing notification since connectionResult is not user-facing: ConnectionResult{statusCode=DEVELOPER_ERROR, resolution=null, message=null, clientMethodKey=null}

[...]

02-22 21:13:36.728  4888  7220 I CAR.SETUP.SERVICE.LITE: quit handler thread
02-22 21:13:39.888  4888  7281 W XFER.Proxy.LITE: Forward throttled, dropping packet
02-22 21:13:39.901  4888  7281 I CAR.GAL.GAL.LITE: Car requests protocol version htr[majorVersion=1, minorVersion=5]
02-22 21:13:39.902  4888  7281 I CAR.GAL.GAL.LITE: Requested protocol version htr[majorVersion=1, minorVersion=5], negotiated protocol version htr[majorVersion=1, minorVersion=7] (STATUS_SUCCESS)
02-22 21:13:39.909  6273  6835 I GH.ConnLoggerV2: Session 9a974462-f24f-4485-bbd7-39a05e302377, event 75, detail OptionalInt.empty, VERSION_NEGOTIATION_STARTED, at 256336 
02-22 21:13:39.920  6273  6835 I GH.ConnLoggerV2: Session 9a974462-f24f-4485-bbd7-39a05e302377, event 76, detail OptionalInt.empty, VERSION_NEGOTIATION_SUCCESS_USB, at 256345 
02-22 21:13:39.935  6273  6835 I GH.ConnLoggerV2: Session 9a974462-f24f-4485-bbd7-39a05e302377, event 77, detail OptionalInt.empty, VERSION_NEGOTIATION_SUCCESS, at 256351 
02-22 21:13:39.938  4888  7281 W CAR.GAL.SECURITY.LITE: Phone will wait for car to send more SSL handshake data
02-22 21:13:39.938  4888  7281 I CAR.GAL.SECURITY.LITE: Final result: java.nio.HeapByteBuffer[pos=0 lim=2377 cap=2377]
02-22 21:13:39.969  4888  7280 W CAR.GAL.GAL.LITE: IO exception, dataReceived=true, isWireless=false
02-22 21:13:39.969  4888  7280 W CAR.GAL.GAL.LITE: java.io.IOException: read failed: EIO (I/O error)
02-22 21:13:39.969  4888  7280 W CAR.GAL.GAL.LITE: 	at libcore.io.IoBridge.read(IoBridge.java:631)
02-22 21:13:39.969  4888  7280 W CAR.GAL.GAL.LITE: 	at java.io.FileInputStream.read(FileInputStream.java:353)
02-22 21:13:39.969  4888  7280 W CAR.GAL.GAL.LITE: 	at hsb.run(SourceFile:108)
02-22 21:13:39.969  4888  7280 W CAR.GAL.GAL.LITE: Caused by: android.system.ErrnoException: read failed: EIO (I/O error)
02-22 21:13:39.969  4888  7280 W CAR.GAL.GAL.LITE: 	at libcore.io.Linux.readBytes(Native Method)
02-22 21:13:39.969  4888  7280 W CAR.GAL.GAL.LITE: 	at libcore.io.Linux.read(Linux.java:231)
02-22 21:13:39.969  4888  7280 W CAR.GAL.GAL.LITE: 	at libcore.io.ForwardingOs.read(ForwardingOs.java:624)
02-22 21:13:39.969  4888  7280 W CAR.GAL.GAL.LITE: 	at libcore.io.BlockGuardOs.read(BlockGuardOs.java:325)
02-22 21:13:39.969  4888  7280 W CAR.GAL.GAL.LITE: 	at libcore.io.ForwardingOs.read(ForwardingOs.java:624)
02-22 21:13:39.969  4888  7280 W CAR.GAL.GAL.LITE: 	at libcore.io.IoBridge.read(IoBridge.java:621)
02-22 21:13:39.969  4888  7280 W CAR.GAL.GAL.LITE: 	... 2 more
02-22 21:13:39.976  6273  6835 I GH.ConnLoggerV2: Session 9a974462-f24f-4485-bbd7-39a05e302377, event 78, detail OptionalInt.empty, FRAMER_READ_IO_EXCEPTION, at 256411 
02-22 21:13:39.980  4888  4888 I GH.CarConnSession: Tearing down
02-22 21:13:39.985  6273  6835 I GH.ConnLoggerV2: Session 9a974462-f24f-4485-bbd7-39a05e302377, event 79, detail OptionalInt.empty, USB_FD_CLOSED, at 256414 
02-22 21:13:39.986  4888  7279 E CAR.SETUP.LITE: ProjectionErrorCode = PROTOCOL_IO_ERROR(3), ProjectionErrorDetail = READER_CLOSE(52), io error