AC problems. Had mechanic check unit out. NO leaks, no mechanical issues with compressor or components. Relay works when bypassed: NO AC, electric issues?

I agree a service manual would be a great place to start... PCM seems like a good reference point, will have to learn more about that. I will check on the underhood fan later this am. Thank you. (i will have to find out what a "underhood fan is first!) thanks

'underhood fan' means exactly that...the fan under the hood! --as opposed to the 'blower motor fan , inside the car. I know on Honda systems the compressor clutch will not be 'commanded on' by the pcm , until it sees both the condenser fan(underhood) and the blower motor(inside) come on. Some models wait a few seconds and then IF they don't see the (interior) blower motor 'on' , THEN it disengages the clutch. The exact order of any of those operations (or neglect of) is the BEST reason why the factory service manual is best for diagnosis(especially if this is not an everyday thing for you! )Best of luck , any further questions continue to reply here and I will check.

Yes the undertake hood fans work EACH time i push the AC button on the dash. BUT the compressor does not kick in. SO i'm wondering if it's the high or low pressor sensor? AND, how do i check it myself, if possible?? I do appreciate you help. I'm hoping it's a sensor rather than a mother board, or PCM (?) board. Question: where can i find the H, L sensor, and can i trouble shoot it myself? Thanks a ton.

I'm only familiar with Honda , However , before buying parts , start with some tests! IF and only IF it is safe , test the field coil( Clutch magnet-should be a single wire to the clutch) for power when the A/C is switched on and the fans are running. mind you , I don't know if subaru uses a thermal protector(like a fuse) in-line , if they do , you definitely need an electrical diagram!! Verify all basic wiring circuits first . I've never personally used it , but if the factory service manual is impractical , and you can't get your local dealer to supply a print-out of just the A/C circuit , then "alldatadiy.com" may be a good source for the basic electrical info.

thanks again, and your caution is noted. I have an appointment with service manager tomorrow- so can i ask you a few more questions? What should i ask the mechanic to look for, and what should i be looking for? Last word from him was the system was "tight, and no leaks" the compressor would work if and when he was able to bypass it; all the components were ok and functional-- and it will probably be in the wiring. So can you given me a little guide as what "electrical" scavenger hunt i am in for?