Perkins M190C - Engine Speed;Timing Sensor Circuit - Test

154 KENR9126
Troubleshooting Section
i04010992
Engine Speed/Timing Sensor
Circuit - Test
System Opera
tion Description:
Use this procedure to troubleshoot the system under
the followi
ng conditions:
•
Use this procedure if another procedure has
directed yo
u here.
•
The engine will not start and the electronic service
tool indic
ates a faulty sensor by displaying “Not
Detected” against the faulty sensor on the “No
Start Parameter” screen.
•
There is an active diagnostic code or a recently
logged diagnostic code that is related to the
followin
g:
•
0190-08 Engine Speed Sensor abnormal
frequen
cy, pulse width, or period
•
0342-08 Secondary Engine Speed Sensor
abnorma
l frequency, pulse width, or period
The engine uses two engine speed/timing sensors.
The pri
mary sensor is located on the left-hand side of
the cylinder block close to the flywheel housing. The
secondary speed/timing sensor is mounted on the
fuel ra
il pump. The primary speed/timing sensor that
is mounted on the cylinder block generates a signal
by detecting the movement of the teeth that are
locat
ed on the timing ring. The timing ring is mounted
on the crankshaft. The signal that is generated by
the primary speed/timing sensor is transmitted to the
Elect
ronic Control Module (ECM). The ECM uses the
signal from the sensor to calculate the position of the
crankshaft. The signal is also used to determine the
engi
ne speed.
The secondary speed/timing sensor is located in
the f
uel rail pump . The secondary speed/timing
sensor generates a signal that is related to the
camshaft position. The f uel rail pump is mechanically
con
nected to the camshaft. The secondary
speed/timing sensor detects the movement of the
teeth on the timing wheel in the fuel rail pump. The
sig
nal that is generated by the speed/timing sensor
is transmitted to the ECM. The ECM calculates the
speed and the rotational position of the engine by
us
ing the signal. The secondary speed/timing sensor
is required for starting purposes.
Du
ring normal operation, the secondary speed/timing
sensor is used to determine the cycle that the
engine is on. When the timing has been established,
t
he primary speed/timing sensor is then used to
determine the engine speed and the angular position.
The loss of signal to the primary sensor and/or the
secondary sens
or will result in one of the following
faults:
•
The loss of sig
nal from the secondary speed/timing
sensor during start-up will prevent the engine from
starting.
•
The engine will continue to run when only one
sensor signal is present from either the primary
sensor or th
e secondary sensor.
•
The loss of signal from the primary speed/timing
sensor duri
ng operation of the engine will result in
engine operation with a derate.
•
Loss of sig
nal from the primary sensor and the
secondary sensor during operation of the engine
will cause fuel injection to be terminated and the
engine wil
lstop.
The primary sensor and the secondary sensor are
intercha
ngeable components. If a sensor is suspect
the sensors can be exchanged in order to eliminate
a fault. If a secondary sensor is suspect and a
replacem
ent secondary sensor is not available, then
the primary sensor and the secondary sensor can be
exchanged. This will allow testing to determine if the
seconda
ry sensor is faulty.