Milan FWD L4-2.3L (2008)
Brake Switch (Cruise Control): Description and Operation
Brake Pedal Position (BPP) Switch
Typical BPP Switch
The BPP switch is sometimes referred to as the stoplamp switch. The BPP switch provides a signal to the PCM indicating that the brakes are applied.
The BPP switch is normally open and is mounted on the brake pedal support. Depending on the vehicle application the BPP switch can be hardwired
as follows:
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to the PCM supplying battery positive voltage (B+) when the vehicle brake pedal is applied.
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to the antilock brake system (ABS) module, or lighting control module (LCM), the BPP signal is then broadcast over the network to be received
by the PCM.
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to the ABS traction control/stability assist module. The ABS module interprets the BPP switch input along with other ABS inputs and generates an
output called the driver brake application (DBA) signal. The DBA signal is then sent to the PCM and to other BPP signal users.
Brake Pedal Switch (BPS)/Brake Deactivator Switch
The BPS, also called the brake deactivator switch, is for vehicle speed control deactivation. A normally closed switch supplies battery positive voltage
(B+) to the PCM when the brake pedal is not applied. When the brake pedal is applied, the normally closed switch opens and power is removed from
the PCM.
On some applications the normally closed BPS, along with the normally open BPP switch, are used for a brake rationality test within the PCM. The
PCM misfire monitor profile learn function may be disabled if a brake switch concern occurs. If one or both brake pedal inputs to the PCM is not
changing states when they were expected to, a diagnostic trouble code (DTC) is set by the PCM strategy.
