Theory Of Operation

The Electric Vacuum Pump (EVP) system is installed to provide supplemental vacuum to the brake booster, when the engine vacuum supply is low. The pump is connected to the engine and the brake booster through a series of hoses and one-way flow check valves. A pressure sensor, mounted in the brake booster, provides information to the ABS/ESP Module. This information is then sent to the Powertrain Control Module (PCM) over the CAN C BUS. The PCM modulates the EVP operation to maintain the brake booster vacuum within a given range. This system ensures that the customer experiences a consistent brake pedal feel under all driving conditions.