System Self-Test
WARNING: This page is about a different car, the 2009 Dodge Durango and 2009 Chrysler Aspen. However, it is still accessible from the selected car via links, so may be relevant.
When the ignition switch is turned-on the microprocessor is tested. If an error occurs during the test, a DTC will be set into the memory. However it is possible the DTC will not be stored in memory if the error has occurred in the module were the DTC's are stored.
The ABM contains a self check program that illuminates the ABS and ESP warning lights when a ABS system fault is detected. If only the ESP light is illuminated ESP system fault is detected. Faults are stored in memory and are accessible with the scan tool.
System faults remain in memory until cleared, or until after the vehicle is started approximately 50 times. Stored faults are not erased if the battery is disconnected.