AC turned on my check engine light!! HELP

[hotmilk400]

Okay, so ever since I got my car, it has been missing the AC, REAR defrost, and Outside air button (the 3 on the right, next to the air controls) it is a 1998 318ti hatchback.

Anyway, it hit 104 degrees in PA this last week, and my driver side door is smashed and the window doesn’t work (so I can’t roll it down) leaving me the sunroof and the passenger side window... I am ready to die by the time i get anywhere, and I am covered in sweat (it doesn’t help that the interior is pure black leather)
okay, so u got the idea. Anyway, I am looking for the missing switch, but it was hard to find one. Today, i got the bight idea to look for wiring diagrams for my car. i found the switch in the diagram, and it seemed easy enough to just jump over, which would turn on my ac without the switch.

it was basically, 1 hot, with 3 outputs, also light outputs, and a ground. I jumped the hot to the ac, and my ac turned on (the rpms dropped, the air was cold) I left it run for awhile without problems. (1 minute idle) I disconnected it and reconnected it a few times, worked every time.. i tried to install a switch with a led, and when i did, it shorted out the fuse (I don’t know why) anyway, I replaced the fuse, and when i hooked up the ac again, the 2nd time i touched it together, the CHECK ENGINE light turned on out of no where.. also, I don’t know if it did it before, but now the engine makes a funny sound when u turn on the AC (like it is injecting a spray of gas) but only does it once right after u flip the switch ( I don’t know if it did it before, but I don’t think it did) .. Now, don’t get me wrong, the ac works great yet, but did i mess up something else up now that it makes the sound, and the check engine light turned on?? (Does it make the sound normally? Someone check for me please) maybe i wrecked a relay?? Please help me out!!!

--- Update
Oh, also, i dont know if this will help, but when i bought the car, the check engine light was on (or turned on shortly afterwards) and later turned off for no reason like 2 weeks later... i i be seeing a problem reacurring because of the ac turning on or something?

.. also, i get around 30 mpg, and i have a 4cly stick shift.. so is that good, or bad? just woundering .. i just changed my air filter like 4 weeks ago (had a chimpmonk/mouse living in it)