Perkins 1104D NH1 Systems Operation Testing And Adjusting page 44

44 RENR7967
Systems Operation Section
Throttle Position Sensor – The throttle position
sensor is an electronic sensor that is usually
connected to an accelerator pedal or a hand lever.
This sensor sends a signal to the ECM that is used
to calculate desired engine speed.
Throttle Switch – The throttle switch sends a signal
to the ECM that is used to calculate desired engine
speed.
Timing Calibration – The timing calibration is the
adjustment of an electrical signal. This adjustment is
made in order to correct the timing error between the
camshaft and the engine speed/timing sensors or
between the crankshaft and the engine speed/timing
sensors.
Top Center Position – The top center position refers
to the crankshaft position when the engine piston
position is at the highest point of travel. The engine
must be turned in the normal direction of rotation in
order to reach this point.
Total Tattletale – The total tattletale is the total
number of changes to all the parameters that are
stored in the ECM.
Wait To Start Lamp – This is a lamp that is included
in the cold starting aid circuit in order to indicate when
the wait to start period has expired. The glow plugs
have not deactivated at this point in time.
Wastegate – This is a device in a turbocharged
engine that controls the maximum boost pressure
that is provided to the inlet manifold.
Wastegate Valve – The wastegate valve regulates
the pressure in the inlet manifold to a value that
is determined by the ECM. The wastegate valve
provides the interface between the ECM and the
mechanical system that regulates inlet manifold
pressure to the desired value that is determined by
the software.