P0703 - Brake Switch Circuit Input Malfunction

WARNING: This page does not describe the selected car, but rather 30 other vehicles, including the 2004 Mercury Sable, 2004 Mercury Mountaineer, 2004 Mercury Monterey, 2004 Mercury Marauder, and 2004 Mercury Grand Marquis. However, it is still accessible from the selected car via links, so may be relevant.

P0703 - BRAKE SWITCH CIRCUIT INPUT MALFUNCTION

Description:	Indicates the PCM did not receive a brake pedal position (BPP) input.
Possible Causes:	Open or short in the BPP circuit. Open or short in the stoplamp circuits. Damaged PCM. Malfunction in module(s) connected to the BPP circuit (rear electronic module [REM] for Freestar/Monterey, LS, and Thunderbird or lighting control module [LCM] for Town Car). Damaged brake switch. Misadjusted brake switch.
Diagnostic Aids:	Check for proper function of the stoplamps. Using the diagnostic tool, check the BPP PID. The stoplamps and PID should toggle on and off with brake pedal activation.
Application	Key On Engine Off	Key On Engine Running	Continuous Memory
Town Car	REFER to the appropriate EXTERIOR LIGHTING article for further diagnosis of the lighting control module LCM system. Make sure the break pedal was applied and released for the KOER self-test and the break pedal was applied for the KOEO self-test.	REFER to the appropriate EXTERIOR LIGHTING article for further diagnosis of the lighting control module LCM system. Make sure the break pedal was applied and released for the KOER self-test and the break pedal was applied for the KOEO self-test.	REFER to the appropriate EXTERIOR LIGHTING article for further diagnosis of the lighting control module LCM system. Make sure the break pedal was applied and released for the KOER self-test and the break pedal was applied for the KOEO self-test.
Freestar/Monterey	REFER to the appropriate EXTERIOR LIGHTING article for further diagnosis of the Smart Junction Box (SJB). Make sure the break pedal was applied and released for the KOER self-test and the break pedal was applied for the KOEO self-test.	REFER to the appropriate EXTERIOR LIGHTING article for further diagnosis of the Smart Junction Box (SJB). Make sure the break pedal was applied and released for the KOER self-test and the break pedal was applied for the KOEO self-test.	REFER to the appropriate EXTERIOR LIGHTING article for further diagnosis of the Smart Junction Box (SJB). Make sure the break pedal was applied and released for the KOER self-test and the break pedal was applied for the KOEO self-test.
Expedition, Navigator	REFER to the appropriate ANTI-LOCK CONTROL article for further diagnosis of the cause of the incorrect brake pedal status from the ABS to the PCM. Make sure the break pedal was applied and released for the KOER self-test and the break pedal was applied for the KOEO self -test.	REFER to the appropriate ANTI-LOCK CONTROL article for further diagnosis of the cause of the incorrect brake pedal status from the ABS to the PCM. Make sure the break pedal was applied and released for the KOER self-test and the break pedal was applied for the KOEO self -test.	REFER to the appropriate ANTI-LOCK CONTROL article for further diagnosis of the cause of the incorrect brake pedal status from the ABS to the PCM. Make sure the break pedal was applied and released for the KOER self-test and the break pedal was applied for the KOEO self -test.
All Others	GO to FD: Brake Pedal Inputs STEP 2	GO to FD: Brake Pedal Inputs STEP 1	GO to FD: Brake Pedal Inputs STEP 3