Self-Diagnostic System: Notes

WARNING: This page is about a different car, the 1995 Plymouth Voyager, 1995 Plymouth Grand Voyager, 1995 Dodge Grand Caravan, 1995 Dodge Caravan, and 1995 Chrysler Town & Country. However, it is still accessible from the selected car via links, so may be relevant.

Self-diagnostic system, if properly used, can simplify testing. PCM monitors several different engine control system circuits.

If a problem is sensed in a monitored circuit, fault code will be stored in PCM and MIL will come on, provided specific criteria are met. PCM will then enter limp-in mode, substituting information from other sources to compensate for component failure. Vehicle is operational in limp-in mode, but driveability may not be optimal.

A specific fault code results from a particular system failure. Fault code only indicates problem circuit. It does not identify specific component failure in the circuit.

If problem is repaired or ceases to exist, PCM automatically clears fault code after 50 ignition on-off cycles . Fault codes can also be cleared using DRB. See ERASING FAULT CODES procedure under ON-BOARD DIAGNOSTICS .