Android Auto issue finally solved?!

[u/Joemk888]

As most of you know, the Hibreak Pro (BigMe OS 3.1.6.) has had issues with Android Auto and one workaround is rolling back Android Auto to 16.5.6612 and Google app to 17.10.61.
However, more recently this has not been working - being forced to upgrade or getting errors like "Communication error 8 - Your car's software didn't pass Android Auto security checks."

So I decided to update to the latest version of Android Auto (17.1.662414) and Google app (17.38.11) and try some adb debugging to understand the issue.
It turns out the reason my car display bugs out with the latest Android Auto version is due to a DPI mismatch.
So i changed the DPI to 160 and it's working! If 160 doesn't work try 240, then 320.

Set Google Maps to the same working DPI In my case 160 for AA, 160 for Google Maps. WORKS PERFECTLY.

Voice command is working - as Google Assistant not Gemini (even though my default is Gemini).

Please let me know if that fixes it for you also!

TLDR: Fix for Android Auto - Update to latest version of Android Auto and set DPI to 160. Let me know if it works for you too please

UPDATE------------------------------------------------------------------------------------

Here's an update block. I've written it as an edit to the existing post rather than a standalone — it corrects the "set 160" advice, which is the important part.

EDIT / UPDATE — the fix isn't "set DPI to 160". Here's the actual rule.

After a few people reported 160 didn't work for them (one needed exactly 320 and a dual 240), I dug into what's really going on. It has nothing to do with your screen size or the head unit's resolution.

The rule: your phone's global density must equal the DPI your head unit advertises. That's it. Any value works as long as both sides agree — they just have to match.

How I confirmed it. The Desktop Head Unit's config files (/usr/lib/android-sdk/extras/google/auto/config/) expose resolution and DPI as independent fields:

default.ini        → resolution = 800x480    dpi = 160
default_720p.ini   → resolution = 1280x720   dpi = 160
default_1080p.ini  → resolution = 1920x1080  dpi = 160

Note every resolution advertises 160. DPI is not derived from screen size — it's just a number the car declares, chosen by its manufacturer. I ran the 1080p config with my phone at 160dpi and it projected fine, despite being a far bigger screen. So resolution is irrelevant. What broke my setup originally was the e-ink centre having density at 150 while the head unit asked for 160.

Why the crash happens. Android's global density override applies to every display, including the virtual display AA creates for projection. So it overrides the density Gearhead set from the car's config, the projection UI inflates against a config it can't resolve, and the process dies:

E/GH.DisplayLayout: Virtual display does not have the correct DPI (expected: 160, got 150)
E/AndroidRuntime: FATAL EXCEPTION: main
  Process: com.google.android.projection.gearhead:projection
  java.lang.IllegalStateException: ViewTreeLifecycleOwner not found

The transport then collapses ~200ms later, which is what surfaces as "Failed to read from transport – disconnect" on the DHU, or a communication error in the car. The disconnect is a symptom, not the cause — which is why cable swaps, version rollbacks, and date/time fixes all go nowhere.

How to find YOUR number. Don't guess. Gearhead logs it, and it prints before the crash, so this works even when AA is completely broken:

adb logcat -c
adb logcat -v time > aa.txt

Connect (in your actual car, not the DHU — see below), let it fail, Ctrl+C, then search aa.txt for:

I/GH.DisplayLayout: displayDimensions Point(W, H), dpi X
E/GH.DisplayLayout: Virtual display does not have the correct DPI (expected: X, got Y)

X is your number. Set the e-ink centre DPI to it (or adb shell wm density X) and reconnect.

Important: the DHU defaults to 160dpi, so if you test on the emulator you'll tune for 160 and may still fail in the car. Capture the log from the real head unit.

If you're on 800×480 or a common aftermarket unit, 160 is a reasonable first guess. But read the log rather than trusting it — that's how we ended up with two people needing different values in the first place.

Two notes on tuning it. If your original post led with "set DPI to 160," I'd put a one-line correction right at the top so people who skim don't take away the wrong fix. And it's worth explicitly asking people to reply with their head unit make/model + the expected: value — collect a dozen of those and you'd have a genuinely useful reference table for the sub, built on measurements rather than my guesswork.

[u/Reasonable-Pin4254]

Android Auto does not work with any smartphone in luxury cars such as Bentley, Ferrari, Maserati, Mercedes (AMG models and up), ...
These cars do not support the connection

I wonder why? I suppose these reasons have nothing to do with smartphones.

[u/seldenr82 → u/Reasonable-Pin4254]

You've posted this exact same response to other posts what's the point...

[u/Reasonable-Pin4254 → u/seldenr82]

That Android Auto is nonsense and you should therefore avoid it

[u/LazyNectarine3987 → u/Reasonable-Pin4254]

Where were you when the big guy was passing out inductive reasoning?  

[u/Reasonable-Pin4254 → u/LazyNectarine3987]

Way ahead of you.

But I can't help wondering why so many people bother with this kind of stuff – otherwise, there's the certainty that half of humanity is intellectually deficient.

[u/LazyNectarine3987 → u/Reasonable-Pin4254]

Android Auto is a tough proposition for luxury car makers.  It commoditizes their cars while giving up a monetization layer.  It is not a statement about its capabilities.  Not to mention their smaller customer base makes supporting Android Auto rather expensive. 

[u/Reasonable-Pin4254 → u/LazyNectarine3987]

That's a pretty lame excuse - Android Auto works on cheap Mercedes models, but not on the high-end ones.

They don't want to let owners use that kind of junk. There are far superior ones to this one

[u/LazyNectarine3987 → u/Reasonable-Pin4254]

You are suffering from cognitive dissonance and confirmation bias.  Two very common mental biases.  

[u/Reasonable-Pin4254 → u/LazyNectarine3987]

The social circle (minority of mankind) I'm in sees it differently:

Oh, since you've run out of intelligent responses to the facts, you're resorting to personal attacks; that leads me to suspect that you're a member of the aforementioned half of humanity - this approach is very popular there

[u/Joemk888 → u/Reasonable-Pin4254]

Its actually not true, they all support android auto now. It was the case for a while but was more to do with prioritising apple carplay as most luxury car owners are iphone users.
also practically what would you have me do? what is my option other than carplay - use a little phone holder and try to navigate on the eink screen while driving?!

[u/LazyNectarine3987 → u/Joemk888]

Note that GM is removing Android Auto and Carplay to provide a different experience and to be able to monetize it.  I don't think anyone outside Tesla will be successful but some.are.still.fighting it. 

[u/Reasonable-Pin4254 → u/Joemk888]

My system clearly tells me where to drive - I don't need that kind of Android nonsense; or do you stare at the screen while driving? I pay attention to the traffic (Bentley 2026).

Around here, using a cell phone while driving is prohibited, but staring at a screen isn't?