Reading and Clearing Diagnostic Trouble Codes

The self-diagnostic system operates in two modes, a Regular Mode and a Test Mode. In the Regular Mode, components necessary for proper starting and driving are monitored by the control unit. If the control unit detects a malfunction in the Regular Mode, the ESC or Check Engine light will be lit by the control unit.
To diagnose the system, the Test Mode must be accessed. This is done by first turning the ignition OFF and connecting the Test Mode connectors ( two wires with "T" shaped connectors located under the left side dash ). Then turn the ignition ON and read the trouble codes as displayed by the red LED on the control unit which is located under the dash.
Trouble codes are represented by a long flash for the first digit and a short flash for the second digit. For example, code 23 would be represented by 2 long flashes and 3 short flashes. If more than one code is stored in the control unit's memory, the codes will be displayed in numerical order. When the system has been restored to normal operation, the trouble codes will automatically clear from the control unit's memory.