.... And IMO I’d have a hard time to believe the whole instrument cluster needs to be replaced based on these 2 warnings. ....
I would have said +1 to the above, based on just intuition and gut feel alone. And what Mazda wrote about instrument cluster replacement in the service manual IMO makes this appear to likely have been another incompetent stealership wallet cleaning for the owners posting in this thread.
First off, one would expect an instrument cluster to be nothing more than a collection of dials, lights, and gauges, driven by the BCM or another controller. At least that's what I would have expected anyway. Well in this modern age of hyper complex vehicles, nothing ever seems to be a simple as it should be, as indicated by this from the service manual:
"The instrument cluster prior to replacement stores the vehicle specification information."
So it turns out that the instrument cluster itself has some type of chip/controller that stores some vehicle 'specification' data, which is used and required by the instrument cluster to function - i.e. it's the instrument cluster computer
I'm not going to bother including the other service manual information relative to replacing the instrument cluster, and will just summarize it by saying that a M-MDS procedure is required to be performed whenever the instrument cluster is replaced. And the first step of that procedure is to copy the existing 'specification information' from the current vehicle's instrument cluster to the M-MDS, for subsequent loading into the replacement new cluster. And they also state that if the vehicle's instrument cluster specification information cannot be read by the M-MDS, then
"perform the configuration using As-Built data". This last bit means that enough of this cluster specification data must also exist in the other computers to program the new cluster well enough to be able to function correctly. Or how about perhaps reprogram the existing cluster?
Putting all of this together, here's what I suspect might be happening. First off, something during the battery replacement caused the specification data in the instrument cluster controller to get trashed, beyond what a TPMS reset can correct. Then when the Mazda tech plugs the M-MDS in, it tells him/her that the instrument cluster specification data cannot be read. So the tech just automatically concludes that the instrument cluster is shot, and hangs on a new one. Then the tech realizes there's no stored M-MDS data (from the old cluster) to program the new part, and sees the 'As-Built' information, and proceeds to successfully configure the replacement cluster using that option.
The missing piece to the above scenario is of course that they didn't try the 'As-Built' option on the existing vehicle's cluster, before hanging on the new one. But their counsel would offer the defense that there was nothing in the service manual that said to try As-Built on the factory cluster, which means they're most certainly innocent of all charges. And beside that, 'we don't try to repair old parts - we just replace them'.
So IMO here's the bottom line on this for anyone else having this specific problem, and being told by Mazda that the instrument cluster needs to be replaced. Tell them that you want the 'As-Built' configuration option to be tried on the existing cluster, prior to any parts being replaced. And if they don't know what that means, hand them a print out of that procedure from the service manual.
