Isuzu 2008MY N Series Workshop Manual page 385

1A-382 Engine Control System (4HK1)
Barometric Pressure (BARO) Sensor
The BARO sensor is located under the instrument
panel (IP) cluster near the pedal bracket. The BARO
sensor is a transducer that varies voltage according to
changes the barometric pressure. The BARO sensor
provides a signal to the ECM on the signal circuit,
which is relative to the pressure changes of the
barometric pressure. The ECM should detect a low
signal voltage at a low barometric pressure, such as
high altitude place. The ECM should detect high signal
voltage at a high barometric pressure. The ECM uses
this voltage signal to calibrate the fuel injection quantity
and injection timing for altitude compensation.
Boost Pressure Sensor
Legend
1. Boost pressure sensor
469%$-50 "
1
LNW76ESH002801
The boost pressure sensor is located in the air
induction tubing. The boost pressure sensor is a
transducer that varies voltage according to changes in
the air pressure inside the air tubing. The boost
pressure sensor provides a signal to the ECM on the
signal circuit, which is relative to the pressure changes
in the air tubing. The ECM should detect a low signal
voltage at a low boost pressure, such as low engine
load. The ECM should detect high signal voltage at a
high boost pressure, such as high engine load.
Camshaft Position (CMP) Sensor
1
Legend
1. Timing chair sprocket
2. Rotating direction
3. Camshaft position (CMP) sensor
The CMP sensor is installed on the cylinder head at the
rear of the camshaft gear. The CMP sensor detects
total of five holes per one engine cycle (four holes
arranged equally every 90° and one reference hole on
the camshaft gear surface). The CMP sensor is a
magnetic resistance element (MRE) type sensor, which
generates a square wave signal pulse.
2
3
LNW76ESH005501