Disconnect the negative battery cable from the ground stud on the left shock tower. Remove the trim bezel from the instrument panel. Remove the three cluster hood screws from the trim bezel opening. Pry up the cluster hood bezel a few inches to expose the cubby bin screws. Disconnect the wiring and remove the cubby bin. Remove the A/C Switch screws. Lower the A/C Switch into the cubby bin opening and disconnect the wiring harness from the rear of the A/C Switch. Release the cable clips from the top of the A/C Switch. Retain the clips for further use. Disconnect the temperature control and the recirculation control cables. Remove the A/C Switch. Remove the A/C Switch. Using an ohmmeter, measure the resistance between terminals 5 and 8 of the A/C Switch 8-way connector. Turn the A/C Switch to each position and check the resistance as follows: PANEL = 828 to 856 ohms, BI-LEVEL = 1280 to 1300 ohms, FLOOR = 2300 to 2358 ohms, MIX = 5200 to 5300 ohms, DEFROST = 99 to 100 K-ohms. If any resistance is not correct, replace the A/C Switch. If the resistances are correct, check for blown fuses, damaged wiring, bad connections, defective Body Control Module (BCM), or bulkhead connector. Installation is the reverse of removal. If necessary, adjust the cables as follows: Attach the cable to the A/C Switch lever. Rotate the knob fully counterclockwise. Pull the cable housing away from the cable end to remove all freeplay and clip the cable housing to the A/C Switch. Verify the knob travels through its full range.