Recently, the ABS brake flex lines were replaced. When I picked up my car from the shop, the message was showing to check my back brake lights; however, they were working fine, including the middle brake light. When the ABS brake flex lines are replaced, does the sensor get touched or would something else have caused this?
The rear lights, including the brake lights, all go through the light control module and should have nothing to do with the ABS system. You may have bad bulbs. Have them checked to see if one or more brake lights are out and need bulbs. If you need to have this looked at, a certified professional from YourMechanic can come to your home or office to diagnose the Warning Light as well as your brake lights in order to determine what is going wrong.