Powertrain Control Module (Pcm)

The PCM is a digital computer that controls ignition system, air/fuel ratio, emission control devices, cooling fan, charging system, idle speed, and cruise control system (if equipped). PCM uses input signals from various switches and sensors to control output devices in order to achieve optimum engine performance for all operating conditions. See INPUT DEVICES and OUTPUT SIGNALS . Powertrain Control Module (PCM) is located between driver's side front fender and Power Distribution Center (PDC), near battery. See Fig 1 .

PCM contains a self-diagnostic system which stores a Diagnostic Trouble Code (DTC) if an electronic control system failure exists. DTC may be retrieved from PCM for system diagnosis by using a scan tool. See SELF-DIAGNOSTIC SYSTEM .

Fig 1: Locating Power Distribution Center & PCM

Courtesy of CHRYSLER CORP.

NOTE: Components are grouped into 2 categories. The first category covers INPUT DEVICES , which control or produce voltage signals monitored by the PCM. The second category covers OUTPUT SIGNALS , which are components controlled by the PCM.