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Q: Brake lights stay on all the time.

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My brake lights stay on all the time. Running or not. I replaced the brake booster recently. (Twice) I checked the brake light switch. It works. Adjusted it to as close as it would go to the brake pedal. Checked the calipers for leaks. Bled the system. Bled the master cylinder.
Checked the hose from the the vacuum pump. Not with a gauge though. Seemed to be pulling good vacuum. Checked all vacuum hoses for leaks. Pulled the low vacuum sensor. At first the brake lights went off. Now, no effect when I remove it. I have to disconnect the battery when I'm not driving it. .

My car has 110000 miles.
My car has an automatic transmission.

Hi there. The most likely cause for the brake lights staying on is, a faulty brake light switch. Another possibility, would be a short to power past the brake light switch and disconnecting the brake light switch would isolate whether, the short to power is past the switch. Circuit tests should be performed to prove the diagnoses and avoid unnecessary repairs. I recommend having your vehicle’s brake lights stay on be diagnosed and repaired by a certified technician, such as one from YourMechanic.

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