Cause
Blown permanent supply fuse
The fuse on a module's permanent, always-live feed. That supply is what keeps a module's memory and clock alive with the ignition off, so losing it does not stop the module working — it stops it remembering.
The signature is a module that behaves as though the battery were disconnected every time the vehicle is switched off: adaptations lost, clock reset, codes for memory and keep-alive faults on every start. A vehicle that relearns from scratch each morning is describing this, and it is easy to misread as an intermittent module. A fuse is a symptom — find what took it before fitting another, since a permanent live shorting to earth is also a fire risk and will take the replacement too.
Typically an easy fix. Often worth checking before paying anyone to look.
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Codes where this is a likely explanation first, rather than merely a possible one.
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