TAD950-952VE,
TAD1350-1355GE,
TWD1643GE,
TWD1663GE,
TWG1663GE
p0004941
TAD1250-1252VE
Coolant temperature sensor
The sensor is located in the left rear part of the cylin-
der head.
The sensor senses the coolant temperature and
sends the information to the control unit. The sensor
comprises
a
non-linear resistor, where the resistance
is dependant on the temperature of the resistor body.
The resistance drops as temperature rises.
Switch, piston cooling
A
valve
is installed in the oil filter bracket which opens
or closes the oil supply for piston cooling, depending
on oil pressure. If the oil pressure is below 250 kPa
(36.3 PSI) (TAD950-952VE) or 300 kPa (43.5 PSI)
(TAD1250-1252VE), the valve closes the oil supply for
piston cooling.
The piston cooling pressure is monitored by a pressure
monitor. The output signal from the pressure monitor
can only have two distinct positions, on/off, in the same
way as a relay output. The monitor is supplied with
current from the engine control unit. A pre-set pressure
limit of 150 kPa (21.8 PSI) determines when the mon-
itor switches on. The monitor opens if the pressure
exceeds this value.
At idle, the monitor can be closed without a fault code
being set.
Fuel pressure sensor
The sensor measures fuel pressure and is located on
the fuel filter bracket. The sensor is an active sensor,
i.e. the sensor requires a supply voltage of +5 Volt. The
sensor provides an output signal whose voltage is pro-
portional to the pressure that the sensor measures.
30-0 General
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