A QUESTION FOR ANY A/C EXPERT........

[bfdtpkt]

A QUESTION FOR AN A/C EXPERT........

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Does the A/C compressor "kick-off" when the engine temp gets too high?

I've apparently got a slow coolant leak, didn't know it til the A/C "kicked-off", happen to look down and the engine temp gauge was 3/4 HOT.

Stopped, added coolant, engine temp came down, A/C started blowing ICEY COLD again.........

So I'm assuming there is a relay of some sort that turns off the A/C when the engine is HOT ????
Thanks for your help.

[Tech]

it's not really an a/c question. Your BCM controls your a/c request. On the network, if the ECM says there is an overheat condition, it'll start talking to the other control units - reducing engine output, reducing loads (like a/c) and set the MIL. If you'd continued, you'd have experienced a lack of power, until you finally hit fail-safe - where you can't rev over 2200rpm ish

[bfdtpkt]

Would it actually "shut-down" the engine before it seized????
Boy, wouldn't that be a great feature for ANY vehicle......

[Tech]

as far as i know, there isn't any condition that actually "shuts down" the engine in a self-preservation sense. The engine will go to fail safe where you can't rev over 2000ish, beyond that the thing usually runs so bad it just dies, but not because the ECM tells it to.

As for the compressor, you're pretty well protected, unless it has a mechanical fault in it (super super rare) or you happen to get some bad service, where the refigerant level is good enough to turn AC on, but the oil level is so low that it burns up.

The compressor is capable of "free wheeling" when needed via BCM control because the clutch is magnetic. When you start the car and hit the AC button, the click you here is the clutch engaging, controlled by the BCM which sees you requested AC. When the engine temp is out of spec, or the AC charge is too low (or pressure too high, or you just don't want AC on) it denies your request and you get warmer air (equal to turning on the blower in a car without AC).