6E–346
ENGINE DRIVEABILITY AND EMISSIONS
D
Crankshaft position (58X reference).
D
Camshaft position (CMP) sensor.
D
Engine coolant temperature (ECT) sensor.
D
Throttle position (TP) sensor.
D
Knock signal (knock sensor).
D
Park/Neutral position (PRNDL input).
D
Vehicle speed (vehicle speed sensor).
D
PCM and ignition system supply voltage.
D
The crankshaft positron (CKP) sensor sends the
PCM a 58X signal related to the exact position of the
crankshaft.
TS22909
D
The camshaft position (CMP) sensor sends a signal
related to the position of the camshaft.
TS22910
D
The knock sensor tells the PCM if there is any
problem with pre-ignition or detonation. This
information allows the PCM to retard timing, if
necessary.
TS24037
Based on these sensor signals and engine load
information, the PCM sends 5V to each ignition coil.
060RW015
The PCM applies 5V signal voltage to the ignition coil
requiring ignition. This signal sets on the power transistor
of the ignition coil to establish a grounding circuit for the
primary coil, applying battery voltage to the primary coil.
At the ignition timing, the PCM stops sending the 5V
signal voltage. Under this condition the power transistor
of the ignition coil is set off to cut the battery voltage to the
primary coil, thereby causing a magnetic field generated
in the primary coil to collapse. On this moment a line of
magnetic force flows to the secondary coil, and when this
magnetic line crosses the coil, high voltage induced by