Electrical problems affecting air compressor in Jetta?

My car takes a while to get cool but when it does it is ice cold. My repair shop says I have a short in my compressor and it has to be replaced, However, my car also recently got a new starter, shifter assembly, shifter wiring and neutral safety switch due to corrosion from a leaking battery. Then a few weeks later the engine went out as soon as it started so I got a new fuse.
Since then the air conditioning has been fine (although it’s only been a few days). So I was wondering if the air compressor problems could have simply been due to the electrical problems, which are now (hopefully) fixed?

If there was a short in the compressor circuit it would blow a fuse and the A/C wouldn’t work at all. Unless the problem is intermittent I don’t follow the shops diagnosis of the problem.

Whatever caused a fuse to blow out and kill the engine shouldn’t be caused by something within the A/C system. You don’t state which fuse you replaced but things don’t usually just fix themselves.

There’s a lot of stuff going on with this car. I don’t know if your mechanic is really competent, and explains things well, but what you write is fragmentary and hard to follow.

One thing about nomenclature: the car’s compressor is not an air compressor. It compresses a refrigerant chemical mix, formerly Freon, which is liquid or gas depending on its temperature and the pressure it’s under. It’s just called the compressor.

If there was a short in its circuitry, the fuse would blow and the air conditioner would not work. But that blown fuse would not keep the rest of the car from working. So “the engine went out as soon as it started so I got a new fuse” doesn’t make sense. If there was a blown fuse that caused the engine to shut off right after starting, a new fuse would almost certainly blow soon, because the underlying electrical problem is not fixed by replacing a fuse.

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I forgot to say the problem is intermittent. But since I got the new fuse - some kind of main computer fuse - so far so good, the a/c has been cold. I got the fuse 7 days ago. So you don’t think this fuse will last long?

Fuses rarely if ever just happen to blow. They blow because there is damage to the circuit that it protects. When a mechanic finds a blown fuse, the first thing he does is look for what made the fuse to blow. If this is an intermittent problem, this fuse can blow when the problem arises again.

Is the battery on the same side of the engine compartment as the A/C compressor? If so, it’s more likely the AC and battery problem are related. If on opposite sides, more likely a coincidence. I had a battery leak and corrode a wire inside a major wiring harness on my Corolla one time. Very difficult to find which wire it was. But I knew it was related to the alternator, so I finally found it. Not that uncommon of a problem to have. You’d need to have an auto-electric expert look at the car’s electrical schematics to get more clues about what’s related to what.

It is possible there is an intermittent shorting problem within the AC clutch so that fuse may blow out. That would cause the AC to not work but there should be no problem with the engine running if that happens. If the fuse for the ECU power goes out that would be due to a different problem. Possibly due to a problem within the engine sensor power bus circuit, which would kill the engine.

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