The Engine Control Module (ECM) not only monitors the various sensors installed in the vehicle, but it also ensures the proper functioning of other components related to the comfort of the vehicle. In this case, the diagnostic code P0571 OBD2 refers to a fault in the speed control circuit/brake switch A.
The good work of the speed control system is essential so that the circuit may perform well since one of the ways to deactivate or activate the speed control is by pressing the brake pedal.
When this code is set, it indicates a failure within the speed control circuitry. This code refers to the letter “A”. This letter can refer to a cable, connector, or another component. Therefore, to find out what it specifically refers to, you should consult your vehicle’s service manual. You may also want to check the wiring diagram for the cruise control system.