Hmm - not sure. Maybe do the infotainment reset (hold end-call for 10 seconds).
My speed limit display is still working (knock on whatever) - both before and after the Google Maps update. Liftgate also working reliably after the full vehicle software update. Left side of the cluster also now stays on the trip screen between every power cycle - used to only last a couple days before something reset and defaulted to the initial left side screen (not trip display).
My first anomaly since the vehicle full update was yesterday, with the Service Vehicle Soon indicator on and the Li-Ion and 12V battery faults showing in the mobile app. Later today, both the icon in the car and the mobile app faults are gone again.
Perhaps some update triggered the loss of function for your speed limit, and maybe now an underlying fault. Even though OTA updates for the main modules are disabled, some things are still happening like the Android Automotive apps, SuperCruise map updates, and perhaps even the OnStar module. Wonder if something happened during one of those quiet updates.
I'm not clear where the speed limit info comes from or how it gets communicated to the instrument cluster portion of screen (via the radio). The data would seem to be coming from Google Maps, but not sure of the specifics of the hardware and software partitioning in the radio for the left/right side screen content. Maybe
@ElectricAvenue could find some clues.
When my speed limit display got broken after the Android 12 release, I can say they fixed it without doing the infotainment USB update - just the radio and serial data gateway updating. Kinda surprised me - I thought the bigger USB update of the infotainment would be needed. So almost like something was in a fault state. Had this fixed a few months back before the 'March update', and it continued to work afterward as well.
I've ordered a the Topdon TopScan Pro. Will see how that lower cost tool ($100) performs versus the other tool that was mentioned on the OBDII thread. Something like this may shed light if there are hidden faults occuring that may explain some of this. Might be standard equipment to carry in the car - like the 10mm wrench for the 12V battery.
