Cause
Blown brake light fuse
The fuse feeding the brake lights, blown so the lamps and everything sharing the circuit stop working. The brake light circuit does far more than illuminate lamps — it tells the engine module the brake is applied, releases the shift lock, disengages cruise control and is used by stability systems.
So a blown fuse produces a set of unrelated-looking faults at once: a selector that will not leave park, cruise control that will not engage, and a stored brake switch code. A vehicle stuck in park with no brake lights is this, and it is a fuse rather than a transmission problem — which is worth knowing before anything is dismantled.
A fuse is a symptom. Water in a rear lamp cluster, a corroded bulb holder shorting, or a chafed harness at the tailgate hinge are the usual causes. Check the lamp units and the tailgate loom before fitting a replacement — and note that a trailer socket wired incorrectly is a frequent cause on vehicles that tow.
Typically an easy fix. Often worth checking before paying anyone to look.
Codes this can cause (2)
Codes where this is a likely explanation first, rather than merely a possible one.
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