300 V6-3.5L (2008)
Engine Control Module: Description and Operation
Powertrain Control Module - Operation
Operation - PCM
OPERATION - PCM
1. Also refer to Modes of Operation.
The PCM operates the fuel system. The PCM is a pre-programmed, dual microprocessor digital computer. It regulates ignition timing, air-fuel ratio,
emission control devices, charging system, certain transmission features, speed control, air conditioning compressor clutch engagement and idle speed.
The PCM can adapt its programming to meet changing operating conditions.
The PCM receives input signals from various switches and sensors. Based on these inputs, the PCM regulates various engine and vehicle operations
through different system components. These components are referred to as Powertrain Control Module (PCM) Outputs. The sensors and switches that
provide inputs to the PCM are considered Powertrain Control Module (PCM) Inputs.
The PCM adjusts ignition timing based upon inputs it receives from sensors that react to: engine rpm, manifold absolute pressure, engine coolant
temperature, throttle position, pedal value, transmission gear selection (automatic transmission), vehicle speed and the brake switch.
The PCM adjusts idle speed based on inputs it receives from sensors that react to: throttle position, vehicle speed, transmission gear selection, engine
coolant temperature and from inputs it receives from the air conditioning clutch switch and brake switch.
Based on inputs that it receives, the PCM adjusts ignition coil dwell. The PCM also adjusts the generator charge rate through control of the generator
field and provides speed control operation.
NOTE: PCM Inputs:
-
A/C select & request via CAN communication bus
-
Auto shutdown (ASD) sense
-
Brake switches 1 & 2
-
Direct Battery voltage
-
EGR Position sensor
-
EVAP purge solenoid current sense
-
Camshaft position sensor signal
-
Crankshaft position sensor
-
CAN C bus communication for internal module communication and data link connection for scan tools
-
Engine coolant temperature sensor
-
5 volts (primary)
-
5 volts (secondary)
-
Fuel level via CAN communication bus from IPM
-
Generator (battery voltage sense) output
-
Ignition circuit sense (ACC & Run/Start via hardwire from Integrated Power Module (IPM) while the Crank indication is via CAN communication
bus)
-
Intake manifold air temperature sensor
-
Evaporative system ESIM vacuum switch (if equipped)
-
Manifold absolute pressure (MAP) sensor
-
Oil pressure
-
Oxygen sensors signals
-
Park/neutral switch
-
Power ground
-
Sensor return
-
Signal ground
-
Speed control switch states are determined by SCM and transmitted over the bus via CAN bus
-
SRV position sensor signal
-
Throttle position sensors and Pedal value sensors
-
Transmission pressure switch inputs (42RLE)
-
Transmission variable line pressure sensor (42RLE)
-
Transmission temperature sensor (42RLE)
-
Vehicle speed (ABS equipped) via CAN C bus from ABS module
-
Vehicle Speed (Non-ABS) from IPM via CAN C and Trans Turbine sensors (with pinion factor)
NOTE: PCM Outputs:
-
A/C clutch relay
