Computers and Control Systems: Description and Operation

There are two versions of the 6.2L diesel engine and a 6.5L Turbocharged diesel engine used in this vehicle.

Light Duty:
The light duty 6.2L diesel engine utilizes an Electronic Control Module (ECM), with a manual transmission, or a Powertrain Control Module (PCM), with the electronic controlled automatic transmission, to control glow plug operation, exhaust gas recirculation (EGR), exhaust pressure regulator (EPR), housing pressure cold advance (HPCA) for the purpose of controlling emissions.

The light duty 6.2L diesel engine utilizes the Diesel Electronic Control (DEC) system to electronically control the exhaust gas recirculation system, the [1][2]torque converter clutch, and the cold advance and glow plug system. The DEC system is made up of the following components:

^ Control Module (ECM/PCM)
^ Manifold Absolute Pressure (MAP) Sensor
^ Coolant Temperature Sensor (CTS)
^ "Service Engine Soon" Lamp Driver Module
^ EGR Valve
^ EGR Vent Solenoid
^ EGR Solenoid
^ EPR Valve
^ EPR Solenoid
^ Throttle Position Sensor (TPS)
^ Engine Speed Sensor
^ DLC Connector
^ Vehicle Speed Sensor (VSS)
^ Cold Advance Relay
^ Cold Advance Solenoid
^ Glow Plug Relay and Control
^ Glow Plugs

Heavy Duty:
The heavy duty 6.2L and 6.5L diesel engine does not use an ECM or a DEC system. However it does utilize a Transmission Control Module (TCM) to control the 4L80E automatic transmission.