Principles of Operation: Notes

The electronic instrument cluster is operational only when the ignition switch is ON. The electronic vacuum fluorescent displays are powered by a non- repairable internal power supply. The only illumination bulb used, which cannot be installed separately, is for backlighting the transmission range indicator. When the headlamps are turned on, the instrument cluster dims according to the interior lighting control switch position.

The instrument cluster contains digital speedometer/odometer, fuel gauge and engine coolant temperature gauge. The indicator lamp module is housed within the instrument cluster and contains miniature bulb warning indicators for ABS, traction control, brake and hazard. The instrument cluster also contains digital message center display information that is controlled by the message center switch module. For additional information, refer to INFORMATION AND MESSAGE CENTER .

Each time the ignition switch is turned from OFF to ON, the three electronic displays will prove out by momentarily illuminating all of the segments and then turning all display segments off. After prove-out, the three displays will return to normal operation. Prove-out mode indicates that all display segments are operating correctly. After the initial prove-out period with the ignition switch ON, these warning indicators are off with the ignition switch ON (warnings will be on with the ignition switch ON, engine off). The following instrument cluster warning indicators will prove out:

AIR BAG
Charging system
CHECK ENGINE
Safety belt
Oil pressure
Fail-safe cooling
LOW FUEL
SPEED CONTROL
CHECK AIR SUSPENSION
OVERDRIVE OFF
DOOR AJAR
LOW WASHER FLUID
TRUNK AJAR

There are three exceptions to prove-out: high beam and turn signal indicators will not illuminate during prove-out. In addition, the safety belt, CHECK ENGINE, AIR BAG and oil pressure warning indicators will remain illuminated during the blank portion of prove-out and then go blank at the beginning of, or shortly after, normal instrument cluster display. The charging system warning proves out by illuminating when the ignition switch is turned to RUN, before the engine is started.