OPERATING ON-BOARD DIAGNOSTIC SYSTEM
To enter diagnostic mode:
1. Turn ignition "ON."
2. Depress the "OFF" and "WARMER" buttons on the Climate Control Center (CCC) simultaneously and hold until the segment check appears on the Instrument Panel Cluster (IPC).
To get out of the diagnostic mode anytime during the test, depress the "AUTO" or "DEFOG" button, or turn the ignition switch "OFF."
The link below will bring you to the code descriptions:
http://myweb.accessus.net/~090/dtcobd1.html