Cause
Weak battery or charging fault
A battery that can no longer hold charge, or a charging system not replacing what is used. It is recorded as a cause because low system voltage produces codes everywhere — modules browning out, actuators not reaching their targets, communication dropping — and each looks like an independent fault in its own system.
That breadth is the diagnostic signal. A set of unrelated codes appearing together across several modules, often after the vehicle has stood, is a supply problem rather than several coincidental failures. Checking voltage first costs nothing and prevents a long diagnosis of consequences.
Separate the battery from the charging system before replacing either. A battery that will not hold charge overnight and a charging system that never fills it produce the same low voltage — so measure resting voltage after standing, then charging voltage with the engine running and loads applied. Modern vehicles complicate this deliberately: a smart charging system varies output by design, so a voltage that looks low may be correct, and many require a replacement battery to be registered before the system will charge it properly.
Typically a moderate job.
Codes this can cause (3)
Codes where this is a likely explanation first, rather than merely a possible one.
Information, not instruction
CarGeek is a reference, not a service manual. Its pages are written from public sources and from what other people have found, never from a manufacturer's own service information, so they can be wrong or incomplete for your particular vehicle. Some of what they describe carries real risk: high voltage, fuel under pressure, stored energy, hot and moving parts.
Have anything you intend to act on checked by a trained person against the manufacturer's own procedure for your vehicle. Nothing here replaces that procedure.
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