Can I disable the AC Compressor on my '95 Chrysler Concorde?

February 5, 2015 5:49 AM

The AC compressor attempts to run when I start the defroster, presumably to dehumidify the air. For some reason though either the compressor itself or the belt that runs it (and the water pump, I think) is smoking when the compressor is on. I'm not worried about humidity and I can't think of a downside. Is there some safety or reliability reason I shouldn't do this? If not, is it as simple as disconnecting a wire?
posted by Perthuz to Travel & Transportation (7 answers total)

Best answer: As long as the belt is still connected, I don't immediately see an issue. If you pull the plug from the back of it and make sure you tape it up and tie it (zip tie both free ends) securely so it can't short then you should be ok. The plug may well already be isolated but tie it up anyway to prevent it getting munched by something and exposing wires. With no electrical load it is likely it will just free spin but you'd have to check it. Disconnect it, run the engine and the air con and see what happens. I think you'd be ok, though, and it's worth a try. The smoke is likely from an electrical issue in the compressor, so isolating it should remove the issue.

That is, of course, assuming you are correct about compressor being the problem. I assume you have accurately diagnosed the source of the smoke?

Mind you, compressors are only $150 on ebay. So it could be a cheap repair.
posted by Brockles at 6:13 AM on February 5, 2015

Best answer: This happened on my 2002 Taurus. I don't know anything about your car, but in mine the serpentine belt smoked and then broke because the pulley was siezed and wasn't turning. Because the pulley wouldn't turn freely, it was not as simple as switching it off, but I was able to buy a shorter belt and reroute it so that the belt bypassed the compressor. This isn't possible on all cars but it's worth looking into whether it's possible/appropriate on your car because it was way easier than replacing the compressor.
posted by geegollygosh at 6:25 AM on February 5, 2015

Best answer: It's fine. I disconnect the A/C by pulling it's relay on my Tiburon every winter because the A/C overpowers the heat when it's -20 and the windows never defrost otherwise.
posted by Mitheral at 6:37 AM on February 5, 2015

in mine the serpentine belt smoked and then broke because the pulley was siezed and wasn't turning.

That's a very good point. Make sure this is not your issue because if the water pump stops while you are driving when the belt finally gives out, that is Bad (™).
posted by Brockles at 6:48 AM on February 5, 2015

Response by poster: Thanks everyone!

I couldn't quite be certain if the smoke came from the component itself or the belt, but I have confirmed that it only happens when the AC is running. I'm going to get the belt looked at - I definitely agree that I don't want that thing breaking. I'll disconnect and secure the plug, activate AC to confirm, and schedule an appointment with a mechanic to confirm the belt is in good shape!
posted by Perthuz at 7:05 AM on February 5, 2015

If the AC smokes after you have disconnected it electrically, it's more of a case of going straight to the mechanic, rather than 'making an appointment'. If the belt has been smoking for a while doing this and it turns out to be because the pulley is not turning it is likely irreparably damaged already and failure is imminent.
posted by Brockles at 7:56 AM on February 5, 2015

Response by poster: Thanks Brockles - I will check. I know that it does spin freely when AC is not engaged. If there is danger of imminent failure, next stop after disconnecting will be the shop. One way or another I'll get it looked at very soon.
posted by Perthuz at 9:22 AM on February 5, 2015