Crankshaft Position Sensor - DaimlerChrysler LH New Yorker 1994 Electronic Service Manual

8D - 6 IGNITION SYSTEMS
Fig. 15 Camshaft Position Sensor Location—
3.3L Engine
FIg. 16 Camshaft Position Sensor Location—
3.5L Engine
TDC occurs after the camshaft pulse (or pulses) and
after the 4 crankshaft pulses associated with the
particular cylinder. The arrows and cylinder call outs
on Figures 13 and 14 represent which cylinder the
flat spot and notches identify, they do not indicate
TDC position.
The camshaft position sensor is mounted in the
front of the timing case cover (Fig. 15 or Fig. 16).
INTAKE AIR TEMPERATURE SENSOR
The 3.5L engine uses a charge air temperature
sensor, the 3.3L engine does not. The sensor threads
into the intake manifold plenum and measures air
temperature (Fig. 17). The sensor provides one of the
inputs the PCM monitors when it adjust injector
pulse width and spark advance.

CRANKSHAFT POSITION SENSOR

The crankshaft position sensor detects slots cut into
the transmission driveplate extension. There are 3
sets of slots. Each set contains 4 slots, for a total of 12
Fig. 17 Charge Air Temperature Sensor—
3.5L Engine Only
Fig. 18 Timing Slots
slots (Fig. 18). Basic timing is set by the position of
the last slot in each group. Once the powertrain con-
trol module (PCM) senses the last slot, it determines
crankshaft position (which piston will next be at
TDC) from the camshaft position sensor input. The 4
pulses generated by the crankshaft position sensor
represent the 69°, 49°, 29°, and 9° BTDC marks. It
may take the PCM one engine revolution to deter-
mine crankshaft position.
The PCM uses crankshaft position reference to de-
termine injector sequence and ignition timing. Once
the PCM determines crankshaft position, it begins
energizing the injectors in sequence.
The crankshaft sensor is located on the passengers
side of the transmission housing, above the differen-
tial housing (Fig. 19). The bottom of the sensor is
positioned next to the drive plate.
IGNITION COIL
WARNING: THE DIRECT IGNITION SYSTEM GENER-
ATES APPROXIMATELY 40,000 VOLTS. PERSONAL
INJURY COULD RESULT FROM CONTACT WITH
THIS SYSTEM.