System Diagnosis

The engine control system on Monaco and Premier does not have a check engine light, store fault codes or have self-diagnostic capability. The ECU is programmed to monitor several different engine control system circuits. If a problem is sensed with a monitored circuit during SYSTEM TESTS using DRB-II, the tester will display a fault code. See FAULT CODE IDENTIFICATION table. However, Keep Alive Memory (KAM) faults are displayed for the O2 sensor, MAP sensor, throttle position sensor, air temperature sensor, and coolant temperature sensor. See KAM under DIAGNOSING WITH DRB-II & JEEP/EAGLE ADAPTER in this article.

A specific fault code results from a particular system failure. The component in that system is not necessarily the reason for the failure. The code indicates a possible malfunction area, it does not condemn the component itself.