[hotmilk400]

So, i have looked all over and could not fiugre out my AC problem.

When i first got my car, the A/C switch was missing (someone stole the radio). i later bought a used switch, only to find out that my A/C would blow a fuse and shut off. disappointed, i replaced the fuse a few times, and by some miracle, it worked for 1 summer. unfortunately, that was 3 years ago, and it has not worked since.

Now, the problem is different. none of the fuses are blown, and all of the Relays work. I followed a wire diagram and made sure voltage was going to each of the fans and to each of the relays.

The problem i am facing now is the A/C relay. The power source that is suppose to switch on the relay is 7volts all of the time (when the car is on). if you turn the A/C on, it does not change. As you know, the relay should be getting zero volts (i would think) and then 12 volts when you turn on the A/C.

I jumped the A/C and the compressor clutch spins just fine. i did not leave it run long enough to blow out cold air, just in case it would wreck something.

This is a 1998 318ti, manual.

My questions are:

- Is it normal for the DME to give the relay 7 volts when the A/C is turned off?

- How can i test the pressure switch for the A/C?

- I can not test the PSI in the unit, what should i do instead?

- is it safe to run the A/C compressor by force (if i jump the relay), say, if the PSI it to low? would it wreck it if it let it run for awhile?

what would you guys do? bite the bullet and take it to the shop? I am a broke college student, i really can't afford to put more than a few $$ towards fixing this. I can test other things, and i can read wire diagrams like a pro, i just need to know what else i should be looking for. it seems i can narrow it down to a bad DME, Bad pressure switch, or no pressure in the system.