The HVAC (Heater Control Head) must be recalibrated. To perform this procedure follow the steps provided. The engine must be at operating temperature with A/C off.. CALIBRATION / DIAGNOSTICS TEST ENTRY TO INITIATE TESTS: Set Blower motor ON HIGH, Set Mode position to Panel, Open all A/C outlets, Set Temperature to Cold (Both slide pots if equipped), Depress WASH and REAR WIPER button simultaneously for 5 Seconds (Until all LED's light). RESULTS: All LED's will turn on for 5 Seconds, Calibration Test is running when REAR WIPER and INTERMITTENT are alternately flashing. Cooldown test is running if A/C and RECIRC are alternately flashing. Acceptable results is REAR WIPER LED is the only LED flashing. Push Rear Wiper to exit.