Hello,

I have lately experienced for the first time, the A/C fuse in the engine bay blowing. A simple swap that I performed yesterday fixed the problem, until this afternoon when I started the car and once again it had blown. Is there a common problem that is known to cause this? 07 V8 Vantage coupe. This is new, and has never had any issue like it before. No engine work has been recently performed. I suspect the compressor wiring perhaps is shorting intermittently?

Any thoughts? All help is welcome before I take this to the dealer after a new mortgage...I see that the wiring for the fuse is straightforward, fuse 10 --> clutch compressor for the A/C and then ground for the compressor, with a relay ahead of everything else in the fusebox (relay 1).

I am particularly untalented with electricity and generally regard it as the Devil's energy, but would replacing the relay be a reasonable next step?

 

Sounds like an A/C compressor clutch or wiring problem. You may find a good dedicated A/C shop that could check and replace just the clutch assembly which would be less than a complete A/C compressor replacement.

 

I think that is my next step. The consensus between some mechanic friends is new compressor.

It appears to be a Denso 5SA12C 447260-0043 if anyone needs a part number.

 

Shops now days normally won't do a clutch replacement only. They want to do the compressor and clutch as a single unit. If it's the original compressor, you've gotten your money's worth out of it.

 

Curiously, it has only blown two fuses in two days since this started and seems to be fine now. I'll wait to see if it blows another before I throw down for a compressor. Knock on wood.

 

I would not normally write the following, but you do admit to being an electrical novice. Rule 1 of electrical, the answer is Never just replace the fuse. Fuse ratings will be chosen for the system load under worst case conditions and then usually multiply that by at least 2.

Once a fuse blows, there IS a problem, maybe not today, maybe not tomorrow, but soon and for the rest of your life.

House breakers are a little different ( totally different technology, but same purpose). Every time they trip they typically have a lower current at which they trip next time and so once you fix the true problem on that circuit it is common to have to replace the now ‘weak’ breaker.

Philip

 

A note of caution. Internal compressor failure is also a possibility, can happen suddenly or not. This could also blow a fuse.
This can be a big problem due to metal partials being spread throughout the internals of the A/C system, meaning new compressor, and more then likely a new condenser, dryer, filters, plus all A/C lines needing to be flushed.

I would take the advice of "J doubleU" and find a good dedicated A/C shop to have it analyzed soon.

 

Part is on the way, thank you all for the solid advice.