Cause
Blown brake light bulb or corroded holder
A brake light bulb blown or its holder corroded, on a circuit the module monitors by current. The brake light circuit does far more than illuminate lamps — it tells the engine module the brake is applied, releases the shift lock and disengages cruise control.
So one bulb can produce several unrelated-looking faults. A selector that will not leave park, cruise control that will not engage, and a stored brake switch code, all from a dead bulb. A corroded holder is commoner than a blown bulb on a rear cluster that has taken years of water. Check the lamps physically and look for green deposits in the holder, and note that an LED conversion produces the identical code by drawing too little current for the module to detect.
Typically an easy fix. Often worth checking before paying anyone to look.
Codes this can cause (1)
Codes where this is a likely explanation first, rather than merely a possible one.
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