I just inherited an 09 Fit Sport. Seems to be in great shape, except that the AC is blowing warm. I thought I'd knock off the easy stuff first before I take it to a mechanic, so I bought a recharge kit, but that's actually showing an overcharge (the needle is in the red).

I thought I'd check fuses, but the only one I find specifically listed as AC in the manual is a 7.5 amp fuse which is fine. Are there any other fuses involved in the AC system that I should check?

The blower motor works fine and I notice that the engine RPM changes when I activate the AC.

 

If the pressure gets too high in the system it won't run. the home cans are touchy on small systems easy to over fill, I add in small amounts just until it makes green. Or I use my Harbour freight gauge set and an adapter to connect a small can. Let me tweak it right to spec.

The engine rpm changes because the computer is programmed to increase idle a bit to keep it up when running the compressor.

You can look straight down from the top at the compressor and have someone turn it on and off you should hear and see the clutch on the front of the compressor activate and deactivate.

 

If the radiator fans come on when you turn the AC on, but the compressor does not engage, that means the system has enough freon it should have kicked the compressor on and is trying to do so electrically.

The next items to check (not in a particular order) are the clutch relay, power to the clutch coil, resistance of the clutch coil, and air gap between the clutch plate and pulley.

I check if the coil is powered up by holding a long screwdriver near the pulley and see if it is attracted magnetically. That shows me it is powered up. Then I use the screwdriver to push the plate into the pulley....If the compressor engages and starts to cool, the problem is usually the air gap is too large, from wear of the plate and pulley.
See this thread: https://www.fitfreak.net/forums/fit-...-cold-gd3.html

 

Mine was blowing cold then all of sudden went warm. Traced problem to AC relay located inside engine compartment drivers side...in a small sub case with 3 relays in total. Seems to be a rather common problem as dealers have relay in stock.