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Barometric Pressure Sensor: Description and Operation

PURPOSE
Detects changes in barometric pressure corresponding to changes in altitude from sea level and signals the powertrain control module engine (PCME).

OPERATION
PCME measures changes in ambient pressure to compensate for changes in altitude.
The barometric absolute pressure sensor affects the operation of the following PCME output systems and/or devices:
- Fuel injection quantity
- BAC valve (Idle air control valve-idle speed)
- Condenser fan (HIGH speed) relays No.1 and No.2
- Powertrain control module transaxle (torque reduced signal/water thermo-signal)

CONSTRUCTION
Integral component of PCME.