@FastDawg Could you check whether the car’s Hotspot or Wi-Fi feature is active? After reviewing your photos again, it looks like the iPhone connects similarly to Android; first via Bluetooth, then automatically switches to a faster Wi-Fi signal for CarPlay. If active, maybe the ES (Wi-Fi/Hotspot) feature is interfering with the iPhone/CarPlay connection.

Similarly, Android has a feature that identifies known Wi-Fi networks when running on mobile data, switching to them automatically. This can lead to phones abandoning the car’s Wi-Fi to connect to open hotspots; like those free offered by AT&T. There are known cases where that feature has caused Android Auto problems, particularly on old Samsung devices. It’s possible the iPhone has an equivalent function triggering the disconnect issue; although that wouldn’t necessarily explain the separate problem with map data disappearing during refresh.

 

Although both are Lexus Interface systems, the RX350 and your ES350 are using different sets of firmware. So, a VPN with wireless CarPlay working without trouble on the RX does not necessarily mean it'll be trouble free with the ES350 firmware and hardware versions.

If you Google "Can a VPN affect wireless Apple CarPlay?" you can get an AI Overview on the issue and somethings to try to work around or fix VPN caused problems with wireless Apple CarPlay.

While I can agree with the desire to use a VPN for privacy and security, turning off the VPN while trying to use wireless Apple CarPlay with your ES is an essential troubleshoot step you can't avoid. If the gremlins don't occur with the VPN turned off, then you know you'll need to figure out which, if any, of the wireless Apple CarPlay VPN potential fix solutions works without causing gremlins occurring in the Lexus Interface system.

The photo you posted with the:
dialog indicates something isn't working correctly in the Wi-Fi networking department. Unless you activated the AT&T in-car Wi-Fi hotspot subscription, the only Wi-Fi connection is the wireless Apple CarPlay Wi-Fi private network connection. To troubleshoot this you need to eliminate as many complicating Wi-Fi connection factors as practical. The VPN usage is a complicating Wi-Fi connection factor for the CarPlay Wi-Fi private network so turn it off while trouble shooting your gremlin issues.

IIRC, both 4G LTE data communication (DCM communication to the outside world cloud servers) and the CarPlay Wi-Fi private network use TCP/IP protocols. So, an interrupted Wi-Fi connection may result in a locked or broken TCP/IP network stack that freezes DCM data communication also. While one might hope networking software wasn't written with such fragile flaws, no one is claiming Toyota/Lexus software developers write bullet proof software.

 

You're correct in that the wireless CarPlay connection is made in a similar manner as a wireless Android Auto connection is made.

IIRC, wireless Android Auto uses the Wireless Direct protocol to establish a peer-to-peer Wi-Fi network between two Wi-Fi devices without requiring anything else like routers or access points. A wireless CarPlay connection establishes a peer-to-peer Wi-Fi network in a similar manner but uses an Apple private/proprietary protocol instead of the publicly published Wireless Direct protocol for Bluetooth and Wi-Fi device discovery and peer-to-peer network setup.

 

Seems like the dealership isn't going to fix anything as its intermittent. The next step I think is to do their job for them. Lexus has published a TSB on getting DIAG info from the Audio System (MMR) that can be submitted to Lexus Tech Support. Maybe if you can provide them this, the dealership can submit and see if they can replace the unit.
Link to the TSB is here .
Start noting the time/place this is happening. Start getting the log files onto a flash drive. After a while give the dealer the log files. Hopefully a case will be created and they can possibly diagnose the issue.
https://static.nhtsa.gov/odi/tsbs/20...18325-0001.pdf

 

Just a faulty sdcard in the Nav?

 

Is it possible that the ES caught a virus from your Corvette?

 

I've heard that's going around

 

My Corvette performs flawlessly. I've got it up for sale because I don't drive it enough. The dealer where I bought it contacted me yesterday and wanted to buy it and sell it as a CPO C8. That should give you an idea of how it performs. He couldn't offer me enough because of how much GM charges him to list a vehicle as a CPO.

I blocked the guy you originally responded to because of replies like that to my posts. Thanks for quoting him so I can see he's still doing the same things.

 

I think that could be it. My son-in-law contacted a friend there and they do have a diagnostics department to figure these things out. Why they can't figure it out - or maybe haven't looked at it - is beyond me. What it's doing is in my pictures.

Thanks for that. I will talk to my Service Advisor about this. EDIT: I just read the instructions and I have already erased that data by turning off my system with the ****.

 

Every service dept has a diagnostic teck to steer mechanics. He is the one I have mentioned to drive to lunch, home, etc. They have to personally see the problem.

 

My friend, I was just making a corny joke about cars catching viruses. I apologize if it came across otherwise.

 

This generation of ES does not use SD cards for the navigation system map database.

For the 2019 through 2022 model year ES's Dynamic Navigation systems which do have a permanent on-board map database, updating that database involves downloading an update file onto a flash USB drive, inserting that drive into one of the USB data capable ports (one of the two USB-A ports located at the front of the center console), and then invoking the Multimedia system's update function.

 

So, from ’23+, is the map database now fully cloud-based with no on-board storage? That could explain the white re-drawing if the TCP connection is active but data could not be downloaded by the iPhone o DCM.

 

The way I understand it is no not 100% fully cloud as it would be useless if you put in a route and go in areas without coverage. It would have to cache the route to be used offline. That is what google maps does also unless you have downloaded areas.

 

They do now. My son in law, who worked for Lexus as a mechanic and Service Advisor, talked to a former coworker. They discontinued the Diagnostic “teams” when he was working there but have recently started them back up.