2003 ford explorer no heat and clicking in dash board

Clicking sound is your blend door actuator stripping it's gears and failing to open the door that directs the blower air through the heater core. Follow the sound to the actuator and remove it. Install a new one. You may have to remove some panels to get to it. The part is shown below and costs $32 at autozone. Please let me know if you have questions.

I did changed actuator still makes sound only when I turn Egnition on.

Ford Explorer clicking- no heat



Blend door actuator failure is a common occurrence on many older Explorers. The clicking noise is actually caused by a stripped nylon gear constantly attempting to hold open the blend door which mixes the hot and cold air sent to registers on dash. As long as the temperature control setting is in the heat range this actuator will hold the door which wants to be normally closed, open. Air flow when the fan is on helps to hold the door open relieving stress on the gear. However whenever the fan or engine are off and the temp control is in the heat range the small gear must hold the door on its own which eventually leads to failure. My tip is to always return the temperature control to the cooling position whenever heat is not needed or truck is turned off. If you are reading this too late the link below will provide you with step by step instructions to replace actuator. I would recommend an OEM replacement part, it makes it easier to orientate when installing the new one. Did this myself and all went well.