Want. How about if you put the defroster on high setting.

Sound like you have a blown 30 amp fuse for the acc unit.
does it come on intermittently. alot of times on the early cars. The blower motor units would go bad.#1 First see if you have a burned fuse. Its located near the fusebox. In a fusable link. Its a little black plastic cover. Pop it open. You should see a the fuse. almost like paper thin. Make sure it not buned or split in half. Psysically feel it or push on it and see if its solid. If it seems ok.Move on,#2 sometimes. the electrical portion of the igntion switch goes bad. turn the acc setting on high blower speed wiggle the key in the ignititon see if it comes on. If it does, you need a new ignition switch If not step #3. with blower setting still on high,wack the center console pass side,closes to the ac unit,see if it comes on,if not step #4. Remove center wood,remove Ac unit. Make sure all connections are ok,you hear a click noise you said. Sounds like the ac unit is send a compressor signal. Thats good. Meaning the unit is probably ok.
If you tinker with these cars,disconnected the black connector @ AC comressor,blue and green wire, put a test light to it. While turn off and on ac unit. If it lights up. The ac unit is ok. # 5 going to need a new blower motor. Thats the hardest of the steps, you have to remove your wiper assembly.




Hope this detail diagnostics helps you out.






guido

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500E Sold
2006 Mini Cooper S
Modified,pulley,injectors,suspension
2009 E350 Sport AMG package