Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Barometric Pressure Sensor: Description and Operation


The Atmospheric Pressure (PA) sensor, which is built into the ECU, is a silicon diaphragm strain gauge type of pressure sensor. This signal is used by the ECU as a reference signal, and compares it to the signal from the MAP sensor to calculate the engine load condition.