Functional Test/Check

The following quick check procedures should be used to determine if system is operating properly or to verify a complaint. Prior to performing quick check procedures, run engine until normal operating temperature is reached, then stop engine. Cycle ignition switch "ON," "OFF" and "ON" while observing whether the LEDs light and the previously set A/C mode and "guide" temperature reading is indicated.
1. Turn ignition "ON." Wait at least 3 minutes before proceeding to step 2. to allow blower delay timer to time out and "HTR" and "BI-LEV" modes to function.
2. Depress "WARM" key pad switch until display indicates 85°F, then release key pad switch. Again, depress "WARM" switch and ensure display reads 90°F (maximum heat).
3. Depress "COOL" key pad switch until display indicates 65°F, then release key pad switch. Again, depress "COOL" switch and ensure display reads 60°F (maximum cool).
4. Depress "AUTO" key pad switch with displayed selected temperature left at 60°F. If the "AUTO" LED flashes after approximately 5 seconds, a problem exists with the mode actuator.
5. Depress "HTR" key pad switch. If the "HEAT" LED flashes after approximately 5 seconds, a problem exists with the mode actuator.
6. Depress "DEF" key pad switch. The "DEF" LED should light. If the light flashes, a problem exists with the AC/DEF mode actuator.
7. Depress "OFF" key pad switch. The compressor clutch should disengage and fan speed should reduce to zero. If the "OFF" mode LED flashes, a problem with one of the mode actuators is indicated.
8. Depress "ECON" key pad switch. The compressor clutch should be disengaged and "ECON" LED should light. If the light flashes, a problem with one of the mode actuators is indicated.
9. Depress "LO" key pad switch. The "LO" LED should light and fan should be at or decrease to low speed within 10 seconds.
10. Depress "HI" fan key pad switch. The "HI" LED should light and fan speed should increase to maximum within 10 seconds.
11. Depress "EXT TEMP" key pad switch. The "EXT TEMP" LED should light and the display should indicate ambient temperature in degrees Fahrenheit. If LED flashes, either the in-car sensor, OSA sensor or air-mix temperature feedback potentiometer is shorted or open.
12. Depress "EXT TEMP" key pad switch again. The display should read the selected temperature and "EXT TEMP" LED should dim.
13. Set selected temperature on display to 74°F and fan speed to "LO." Depress "BI-LEV" key pad switch, then turn ignition switch "OFF" and wait 5 minutes.
14. Turn ignition switch "ON" and ensure temperature display still reads 74°F.
15. Turn parking light switch "ON," then rotate dimmer rheostat and ensure LEDs, back lit front panel and digital display dims in brightness.
16. On models equipped with rear defroster, depress "R DEF" key pad switch and ensure LED brightens in intensity and rear window defogger grid warms the glass.