Page 1263 - Foton Workshop Manual - Tunland (AT)

ENGINE CONTROL SYSTEM - ATMOSPHERIC PRESSURE SENSOR 11-37

ATMOSPHERIC PRESSURE SENSOR 11

HOW IT WORKS

The atmospheric pressure sensor is mounted to the
main branch beam near the ECM engine harness,
and the atmospheric pressure sensor responds to
atmospheric pressure changes. Atmospheric
pressure will vary depending on the altitude of the
current engine. The atmospheric pressure sensor
has a 5V power supply circuit, a sensor signal
voltage circuit and a loop circuit.The engine control
module (ECM) provides an 5V power supply to the
atmospheric pressure sensor through the NO.1
sensor power circuit. The ECM also provides a
ground to the sensor circuit. The atmospheric
pressure sensor provides a signal to the ECM
through the atmospheric pressure sensor signal
circuit. The signal voltage of the sensor will vary
according to atmospheric pressure. When the
vehicle is working at high altitude, the ECM detects
low signal voltage. When the vehicle is working at
low altitude, the ECM will detect a high signal
voltage.

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