Dodge RAM 1500 1998 Owner's Manual page 1593

14 - 24 FUEL INJECTION - GAS
CRANKSHAFT POSITION SENSOR (Continued)
The sensor is a hall effect device combined with an
internal magnet. It is also sensitive to steel within a
certain distance from it.
A tonewheel (targetwheel) is bolted to the engine
crankshaft (Fig. 5). This tonewheel has sets of
notches at its outer edge (Fig. 5).
The notches cause a pulse to be generated when
they pass under the sensor. The pulses are the input
to the PCM.
Fig. 5 CKP OPERATION - 3.7L V-6
1 - TONEWHEEL
2 - NOTCHES
3 - CRANKSHAFT POSITION SENSOR
4 - CRANKSHAFT
4.7L V-8
Engine speed and crankshaft position are provided
through the crankshaft position sensor. The sensor
generates pulses that are the input sent to the pow-
ertrain control module (PCM). The PCM interprets
the sensor input to determine the crankshaft posi-
tion. The PCM then uses this position, along with
other inputs, to determine injector sequence and igni-
tion timing.
The sensor is a hall effect device combined with an
internal magnet. It is also sensitive to steel within a
certain distance from it.
On the 4.7L V–8 engine, a tonewheel is bolted to
the engine crankshaft (Fig. 6). This tonewheel has
sets of notches at its outer edge (Fig. 6).
The notches cause a pulse to be generated when
they pass under the sensor. The pulses are the input
to the PCM.
Fig. 6 CKP SENSOR OPERATION AND TONEWHEEL
- 4.7L V-8
1 - TONEWHEEL
2 - NOTCHES
3 - CRANKSHAFT POSITION SENSOR
4 - CRANKSHAFT
5.7L V-8
Engine speed and crankshaft position are provided
through the crankshaft position sensor. The sensor
generates pulses that are the input sent to the pow-
ertrain control module (PCM). The PCM interprets
the sensor input to determine the crankshaft posi-
tion. The PCM then uses this position, along with
other inputs, to determine injector sequence and igni-
tion timing.
The sensor is a hall effect device combined with an
internal magnet. It is also sensitive to steel within a
certain distance from it.
On the 5.7L V–8 engine, a tonewheel is bolted to
the engine crankshaft. This tonewheel has sets of
notches at its outer edge (Fig. 7).
The notches cause a pulse to be generated when
they pass under the sensor. The pulses are the input
to the PCM.
REMOVAL
3.7L V-6
The Crankshaft Position (CKP) sensor is mounted
into the right rear side of the cylinder block (Fig. 8).
It is positioned and bolted into a machined hole.
(1) Raise vehicle.
(2) Disconnect sensor electrical connector.
(3) Remove sensor mounting bolt (Fig. 8).
DR