Isuzu 2008MY N Series Workshop Manual page 386

Crankshaft Position (CKP) Sensor
A
Legend
1. Crankshaft position (CKP) sensor
2. Sensor rotor
3. Rotating direction
The CKP sensor is located on the flywheel housing.
The sensor rotor is fixed on the flywheel. There are 56
notches spaced 6° apart and a 30° section that is open
span. This open span portion allows for the detection of
top dead center (TDC). The CKP sensor is a magnetic
resistance element
generates a square wave signal pulse. Detecting the
open span portion from the CKP sensor and one
reference hole from the camshaft position (CMP)
sensor, the ECM determines cylinder #1 compression
TDC to ensure they correlate with each other.
1
2
LNW76ESH002701
1
A
Section A-A
LNW46ESH005301
(MRE) type sensor,
Engine Control System (4HK1)
Engine Coolant Temperature (ECT) Sensor
Legend
1. Engine coolant temperature (ECT) sensor
The ECT sensor is installed to the thermostat housing.
The ECT sensor is a variable resistor and it measures
the temperature of the engine coolant. When the ECT
sensor is cold, the sensor resistance is high. When the
engine coolant temperature increases, the sensor
resistance decreases. With high sensor resistance, the
ECM detects a high voltage on the signal circuit. With
lower sensor resistance, the ECM detects a lower
voltage on the signal circuit.
Fuel Temperature (FT) Sensor
which
Legend
1. Fuel temperature (FT) sensor
2. Fuel rail pressure (FRP) regulator
1
2
1A-383
1
LNW81ASH000401
LNW76ESH001901