Overdrive

I think you have two or maybe three separate problems. The O/D light blinking is telling you that there's a transmission fault detected by the electronic control unit. There should be a trouble code stored and available to a mechanic with a scanner to read it. By saying that the A/C is 'acting up,' you must mean that it's not cooling rather than just not blowing air at you. There are two fans, one for the A/C condenser in front of the radiator and there's one for engine (radiator) cooling. Both fuses are in the 'Main fuse Block' on the left inner fender panel. the engine cooling fan should be a 30A fuse and the A/C a 40A fuse. Check those first for the A/C problem. Does the radiator fan cycle on and off when the engine's running? If not you could overheat the engine. Check that out. If it's just the A/C fan not working, it's possible that you have a blown fuse or that the refridgerant charge is low in the A/C, or that the A/C relay on the left inner fender panel near the fuse block is failing. There's a thermal protector near the A/C compressor which could have activated if the fan hasn't been coming on which could overheat the compressor. It's all controlled by the engine control unit but hopefully that's not the problem. You need a Mazda or transmission specialist for the O/D light and a Mazda or A/C specialist for the A/C. Here's a directrory link for you: http://repairpal.com/mazda-repair-in-las-vegas-nevada