Cause
Faulty brake fluid level sensor
The float switch in the brake fluid reservoir, faulty. The distinction from a genuinely low level is one this diagnosis must get right in the safe direction — believing a faulty sensor over a real leak is how a vehicle is driven with failing brakes.
So confirm the level by eye before concluding anything. The reservoir is translucent with marked levels and takes seconds to check. A sensor reporting low on a full reservoir is a sensor fault; a warning on a genuinely low reservoir is not. The float sticks or its contacts corrode, and the connector on the cap is exposed to under-bonnet conditions. A warning that appears on cornering or braking and clears afterwards usually means the level is genuinely marginal and fluid is moving, which is a real finding rather than a false alarm.
Typically specialist work. Needs equipment or training most home workshops do not have.
Some of these codes mean you should stop driving
1 of the 1 codes this can cause indicate a fault where continuing to drive risks damage or is unsafe. Which one you have matters more than the cause does — read the code's own page before deciding.
Codes this can cause (1)
Codes where this is a likely explanation first, rather than merely a possible one.
Information, not instruction
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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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