[Android Head-Units] vestaviascott:
I'm using the "carlinkit" version of the wireless carplay adapter with a Google Nexus 7 (2013) tablet running ElementalX kernal (for touch to wake and charge+OTG functions).

I'm using this "Y" splitter (Micro USB Y Splitter Cable OTG Power Enhancer Cord USB 2.0 A Female to 90 Degree Micro USB Male and Straight Micro Female On-The-Go Adapter)

With this cable in place, the Carplay Dongle only gets power from the external USB power source, not the tablet battery as would be the case with a single (non splitter) OTG cable (the tablet battery is also getting charged from this external power source, through this cable). If I remove the power source, the little red light on the dongle goes out, and it disappears from the tablet's AutoKit application (where it usually appears as "AutoKit-be5f". I then reconnect the power source and get the little red light on the dongle again, but I cannot get the dongle to resync with the tablet without restarting the tablet.

I can get the carplay sync when I first get into my car and start out, but when I stop somewhere and turn the car off, then get back in the car and start again, the dongle cannot resync with the tablet unless I restart the tablet.

Probably cause?

1) Issue with the tablet's USB permissions or mounting preferences? I'm thinking this is the most likely problem.

2) Issue with the dongle, should auto reset itself once its reconnected to power? Is that the responsibility of the dongle or of the Android USB controller?

3) Issue with the OTG cable (not likely since everything works once just fine when connected for the first time)

So, it seems that when the OTG device loses power, from the car shutting down and the USB power source no longer providing power, the dongle is then dead to the tablet, it does not exist.

But when the power to the dongle is restored, as when I restart my car engine, the dongle is still dead to the tablet. What is supposed to happen here? Does the OTG device send a "I'm here", signal to the tablet or does the tablet continously poll for a live OTG device if one is connected to its micro USB port?

---------- Post added at 05:07 PM ---------- Previous post was at 05:07 PM ----------

I'm using the "carlinkit" version of the wireless carplay adapter with a Google Nexus 7 (2013) tablet running ElementalX kernal (for touch to wake and charge+OTG functions).

---------- Post added at 05:33 PM ---------- Previous post was at 05:07 PM ----------

Update on my findings above. Some progress on diagnosing the problem.

I decided to try this same setup with my Fire HD 8 tablet. The only difference in that setup is that the Fire tablet is stock and not hacked to support OTG+Charging. The Fire HD tablet has NO issues reconnecting the OTG device (the carplay dongle) even after repeated power cycles of the USB power source that's connected to the Y cable.

I've removed the power source, waited several seconds, atleast 15-30 in some cases, reconnected the power source and each time, the Autokit software shows a reconnection of the Autokit-be5f network/dongle and it launches carplay shortly thereafter.

So, with that knowledge, my issue appears to be with the Nexus 7 and specifically, one of two issues:

1) Perhaps the ElementalX "charge+OTG" coding is currupt and cannot resync/mount an OTG device once power is pulled from the OTG device. Restarting the tablet is only option here to get the OTG device going again.

2) The Nexus tablet has an issue remounting an OTG device once power is pulled from the OTG device. Restarting the tablet is only option here to get the OTG device going again.