Cause
Faulty brake booster solenoid
The solenoid used to apply the brake servo under module control, faulty. On vehicles with autonomous braking, adaptive cruise or hill hold, the module must be able to apply the brakes without the driver — this solenoid is how.
Its failure withdraws those functions rather than the brakes. Conventional braking is mechanical and unaffected, so the complaint is assistance systems that have stopped working, with their warning lamps lit together. That cluster with a normal-feeling pedal is the signature. Circuit codes are the winding and the harness, settled at the connector; a performance code with a sound circuit means the mechanism or the vacuum available to it. Check vacuum supply first, since a solenoid commanding an empty reservoir achieves nothing and is not at fault.
Typically specialist work. Needs equipment or training most home workshops do not have.
Codes this can cause (1)
Codes where this is a likely explanation first, rather than merely a possible one.
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