P0703 Mercury 4.6

Question

Engine will die after long coast to stop light or sign. Brake lights work, cruise works. Engine restarts immediately. Replaced IAC. Cleaned throttle body which seems to have helped but not cured.

Answer 1

P0703 Brake pedal position switch

How was this code retrieved, Mercury and Ford uses a KOER (key on engine running) test. if the brake was not applied or applied too much during the test this code occurs. If the cruise and brake light works there is the other circuit that goes to the speed control, the shift lock actuator,and rear electronic module.One of the other job for the BPP is to send a signal to the PCM to disengage the torque convertor clutch when the brakes are applied,The BPP can be ignored if the the TP (throttle position) is not at a closed position. So one of the test to confirm if the BPP is at fault is ,can you shift out of park into drive? If the Brake light work , cruise works, the shift interlock works, this leaves you with the PCM not seeing the brake switch closed, either the the TPS is not at a closed position (there is a idle adjustment screw for the RPM. if it was tampered it can cause this without setting a TPS code.