Work Profile Contacts in Android Auto BYOD

What You've Tried and Why It Makes Sense (but didn't work):

Your troubleshooting steps are comprehensive and logical, indicating you've explored most available options:

Installing Android Auto on Work Profile: Good attempt, but as noted, the core call functionality still seems tied to the personal profile's phone app context within Android Auto.
"Connected Apps" / Contact Sync (Outlook, Gmail): These typically sync contacts within a profile or between the app and the native contacts app within the same profile. They don't inherently bridge the work/personal profile gap for Android Auto's search function.
Default Phone Apps: Changing the default dialer doesn't change the underlying cross-profile data access restrictions.
Work Profile Switch in Android Auto settings: As you observed, this primarily affects notifications and app visibility, not deep contact search.
Searching Work Contacts from Personal Profile Phone App: This works because the phone app on the device itself is designed to handle cross-profile contact lookups if enabled by policy. Android Auto's interface in the car is a different layer of interaction.
Conclusion:

It appears this is indeed a limitation by design to uphold the security and data segregation principles of Android Work Profiles. While the caller ID functionality is often permitted for convenience, full search and browsing of Work Profile contacts from the personal-profile-centric Android Auto interface is generally restricted.

What you can do:

Confirm with your IT Admin/MDM Vendor: Double-check with your organization's IT department or your MDM/EMM vendor (e.g., Microsoft Intune, Google Workspace, VMware Workspace ONE) if there are any specific policies that could enable "cross-profile contacts search" for Android Auto. While unlikely to be a simple toggle for Android Auto itself, they might have insights into broader cross-profile sharing settings.
Voice Commands (Limited): Sometimes, Google Assistant voice commands might be able to dial a work contact if the Assistant has access to the work profile's contacts, even if the visual search doesn't work. This is inconsistent and depends on the Assistant's integration.
Manual Dialing: The most reliable method remains to initiate calls from your phone's Work Profile dialer before connecting to Android Auto, or to manually dial the number in Android Auto if you know it.
Feedback to Google: Given the demand, providing feedback to Google through Android Auto's feedback mechanism is the best way to express the need for this feature.

Ayi NEDJIMI - MCT
www.symplissime.fr