Powertrain Management: Description and Operation

Flow Of Diagnosis:

PURPOSE

Modern computer management systems regulate a variety of subsystems and accessories. Since computer management is complex, it is helpful to divide information into sub-categories as explained below.

INFORMATION STRUCTURE

Information in COMPUTERS AND CONTROL SYSTEMS, FUEL DELIVERY AND AIR INDUCTION, EMISSION CONTROL SYSTEMSand GLOW PLUG SYSTEMS for diesel engines is divided into the following four major topics:

Computerized Engine Controls

Addresses the on-board computer system and components as related to vehicle management. Consult this section for information regarding on-board diagnostics, sensor inputs, computer outputs, etc.

Emission Controls

Addresses emission related systems and components only. Includes (but is not limited to) Exhaust Gas Recirculation (EGR) systems, Evaporative Emission (EVAP) systems, Positive Crankcase Ventilation (PCV) systems, Exhaust Emission controls, Air Injection Systems (AIS), etc.

Fuel Delivery and Air Induction

Focuses on systems and components related to fuel and intake air delivery. Does NOT include information regarding electronic engine controls.

Glow Plugs

Addresses initial cold start and after start functions of the glow plug system. Includes information regarding controllers, relays, circuits and cold advance systems used on diesel engines.