Chrysler RAM TRUCK 2500 1994 Service Manual page 361

8D - 4 IGNITION SYSTEMS
•
, CRANKSHAFT
H POSITION
M SENSOR
SPARK
PLUG
CABLE
LOOM
W I R I N G
A M
HARNESS
J ? 3 1 4 ^ 2 ^
C O N N E C T O R
\
EGR * . TUBE MOUNTING
TUBE / [ BOLTS (2)
Fig. 6 Crankshaft Position Sensor—3.9L V-6 or
5.2/5.9L V-8 Engines—Typical
CRANKSHAFT
POSITION
SENSOR
NOTCHES-
FLYWHEEL
J9314-89
Fig. 7 Sensor Operation—3.9L V-6 Engine
The engine will not operate i f the PCM does not re­
ceive a crankshaft position sensor input.
For component testing, refer to the Diagnostics/Ser­
vice Procedures section of this group.
For removal and installation of this sensor, refer to
the Component Removal/Installation section of this
group.
SENSOR OPERATION*^5.2L/5*9L V-8 ENGINES
On 5.2L and 5.9L V-8 engines, the flywheel/drive
plate has 8 single notches, spaced every 45 degrees,
at its outer edge (Fig. 8).
CRANKSHAF
POSITION
SENSOR
NOTCHES
FLYWHEEL
J93I4-88
Fig. 8 Sensor Operation—5.2L/5.9L V-8 Engines
The notches cause a pulse to be generated when
they pass under the sensor. The pulses are the input
to the PCM. For each engine revolution, there are 8
pulses generated on V-8 engines.
The engine will not operate i f the PCM does not re­
ceive a crankshaft position sensor input.
For component testing, refer to the Diagnostics/Ser­
vice Procedures section of this group.
For removal and installation of this component, re­
fer to the Component Removal/Installation section of
this group.
CRANKSHAFT POSITION SENSOR—8 J L V-10
ENGINE
The crankshaft position sensor is located on the
right-lower side of the cylinder block, forward of the
right engine mount, just above the oil pan rail (Fig.
9).
SENSOm OPERATION—8,01 ¥-10 ENGINE
The crankshaft position sensor detects notches ma­
chined into the middle of the crankshaft (Fig. 10).
There are five sets of notches. Each set contains
two notches. Basic ignition timing is determined by
the position of the last notch i n each set of notches.
Once the powertrain control module (PCM) senses
the last notch, i t will determine crankshaft position
(which piston will next be at Top Dead Center). An
input from the camshaft position sensor is also