Without Scan Tool

1. Turn ignition switch to On position.
2. Simultaneously depress the Off and warmer buttons on the climate control panel and hold buttons until display panel segments are illuminated which indicates the beginning of the diagnostic readout. The purpose of illuminating the two display panels is to ensure all segments are working. If any segments are inoperative, the affected display panel must be replaced.
3. After the display segment check is completed, any stored trouble code will be displayed on the data center. These two-digit diagnostic trouble codes will be displayed with a prefix of either E or F to designate which computer sensed the malfunction. If a diagnostic trouble code is displayed, or if the self-diagnostics system cannot be accessed, a defect has been sensed in the vehicle's electronic control system.
4. After all diagnostic trouble codes are displayed or if no diagnostic trouble codes are stored, the code .7.0 will appear on the display.

DIAGNOSTIC TROUBLE CODE .7.0
Diagnostic trouble Code .7.0 is a decision point. When this diagnostic trouble code is displayed, the diagnostic feature relevant to the current malfunction can be selected. The two diagnostic modes relevant to cruise control diagnosis, ECM switch tests and ECM output cycling, are detailed as follows.