1997 Nissan Altima ac compressor wont engage

Have you checked to see if there is power to the compressor? If you run power directly to it, does it engage?

That I'm not sure how to do with it being installed on the car, I've seen videos of where they used a paper clip in the ac relay to bypass the ac relay, to make it engage. Other then that im not sure where to go next... im at a complele lost for words right now..(by the way the compressor is new)

First, check to see if there is power to the AC cycle switch that you replaced and let me know what you find.

So I have taken the car to a shop, and they said 1st that it was the "Climate Control" , So I had ended up getting 3 of them from "Pick-a-Part", AC Still did not engage. So took it back to the same shop, after they called saying its the cars computer "ECM". I did go take one from another nissan altima altho my dad is wondering if it would do anything to the car..

Is this true that everything working on the car besides the AC is bad due to this ECM being bad only for the AC Compressor???

I'M REALLY CONFUSED...

It could be related to the ECM. However, if the car was in my shop, I would start at the compressor and trace the wiring back until I found where the power was lost. I hate to say it, but when shops just start replacing parts, that tells me they are unsure. As far as the ECM replacement, as long as you got one from the same year, make, and model and it has the same part number, it should be fine. Tell me this, if you run power directly to the compressor, does it engage? I know I asked that before, but I was wondering if you may have tried it. Also, has anyone checked to see if there is even power at the compressor? You could simply have a bad AC clutch that isn't engaging. Just a thought...

They charged me $69.95 i believe
Although they told me that the compressor did in fact engage.. although i have never seen it engage with my eyes.

I assumed this also about the compressor, but i did buy it myself.. and the one that was on the car before did this same thing no power from what it appears. My dad used a volt light tester on the ac relay fuse in the engine bay it got lit on some but the compressor did not engage, although i dont know if he was doing it right or wrong..

There was something i was researching and found this thing that is under the glove box, its a sensor for the temp in the evap??? They said that this fuse tells the ecm what temp the evap is at??? I dont know they name on hand right now.. but i really wish i could get this fixed.

UPDATE: I have seen myself that the AC Compressor DOES infact engage upon jumping the relay with a "Paper Clip". The air blow cold as ice! for the 1st time I've had the car.

There is nothing wrong with AC Compressor this fact has been confirmed by me myself, now as far as the ECU (which is what they told me was the issue.) My ECU has this number "JA18F66" on it there is some I can purchase via eBay.

But I'm wondering if that is the real issue?!

Should I buy a ECU?

If the ECU isn't providing a signal to engage the compressor, yes, it could be the problem. As far as replacement, I don't recommend getting one from ebay. You have no idea what you will be getting.