General System Description

PCM SYSTEM
The Viper uses a Powertrain Control Module (PCM) and Ignition Control Module (ICM) to control the sequential multi-port fuel injection.

The engine systems in this vehicle are controlled by a Powertrain Control Module (PCM) and an Ignition Control Module (ICM). These components provides precise air/fuel mixture control for all driving conditions, and regulates ignition timing, emission control devices, cooling fan, charging system, and idle speed. The PCM and ICM are digital pre-programmed computers that have the ability to update and revise their programming to meet changing operating conditions.

Various sensors provide necessary input for the PCM to function correctly (See list of PCM inputs and outputs below). In addition to these sensors, various switches and relays are used to carry out commands or outputs from the PCM.

The PCM tests many of its own input and output circuits. If a fault is found in any major system, this information is either stored in memory or displayed as a light on the instrument panel. If a fault exists, the fault information can be displayed to a technician through the instrument panel MALFUNCTION INDICATOR LAMP or a suitable diagnostic scan tool.


PCM INPUTS
- Battery Voltage - Brake Switch
- Camshaft Position Sensor - Charge Air Temperature Sensor
- Crankshaft Position Sensor - Engine Coolant Temp Sensor
- MAP Sensor - Heated Oxygen Sensors
- SCI Receive - Throttle Position Sensor
- Vehicle Speed Sensor - Data Link Transmit


PCM OUTPUTS
- A/C Clutch Relay - Alternator Field
- Idle Air Control Motor - ASD Relay
- Fuel Pump Relay - Malfunction Indicator Lamp
- Data Link Transmit - EVAP Purge Solenoid
- Fuel Injectors - Radiator Fan Relay
- Tachometer