User Manual

24 SENR9977
Systems Operation Section
The engine oil pressure sensor is also an active
sensor with thr
ee wires and a power supply. The
sensor provides the ECM with a measurement of
engine oil pressure. The ECM can warn the operator
of possible co
nditions that can damage the engine.
This includes the detection of a blocked oil filter.
The operatin
g range for the engine oil pressure
sensor ....................... 110 to 882 kPa (16 to 128 psi)
Required acc
uracy ......... ±3% of maximum pressure
Temperature
Sensors
g011333 12
Illustration 29
Tempe rature sensor
(1) Negativ
e terminal
(2) P ositiv
e terminal
The intake manifold temperature sensor and
the coolant
temperature sensor are two-wire
passive sensors. The intake manifold temperature
sensor provides the ECM with intake manifold air
temperatu
re so that the ECM can control the fuel for
starting and injection timing. The coolant temperature
sensor provides the ECM with coolant temperature
so that th
e ECM can control injection timing. The
temperature sensors are also used for engine
monitoring.
The operating range for the temperature
sensors ..................... −40° to 150°C (−40° to 302°F)
Required accuracy for sensor ........... ±1 °C (±1.8 °F)
Primary Speed/Timing Sensor
g01133334
Illustration 30
Primary s pee
d/timing sensor
(1) Negative terminal
(2) Pos itive terminal
The primary speed/timing sensor is also a two-wire
passive sensor. The sensor provides the ECM with
the speed an
d the position of the engine from a timing
wheel that is mounted on the crankshaft so that
the ECM can request fuel and timing from the fuel
injection p
ump. The timing wheel has one missing
tooth that is located 70 degrees after top center.
The operati
ng range for the primary speed/timing
sensor ........................................... 142 to 3333 RPM
When the en
gine is cranking, the ECM uses the
signal from the secondary speed/timing sensor in the
fuel injection pump. When the engine is running, the
ECM uses th
e signal from the primary speed/timing
sensor on the crankshaft. This speed/timing sensor
is the primary source of the engine position.
Note: If the primary speed/timing sensor fails, the
engine will be derated and the engine will continue to
operate o
n the secondary speed/timing sensor. Refer
to Troubleshooting, RENR2696 for more information.