The trigger path for your AC is power through a vinyl-covered bullet connector in, with ground returning through the compressor chassis to the engine, and then to the battery. There's a lot more to the circuit on the powered side, but for a quick and easy defeat of the AC compressor, you can just disconnect the bullet connector, and reconnect later when you need AC.

Simple!

Randii (who leaves his connected because the dehumidification is of more value to us with our dog than the heat it costs)

Randii beat me too it. I miss my AC/defroster since I blew up one of the hoses coming back from Moab last year. Get two or three adults in a cold Amigo with the rain or snow here in Denver, and the windows seriously start building up the 'sweat'. It definitely takes a LOT longer to clear them up without the AC compressor helping out.

JEff (who procrastinates at times. I am committed to fixing that hose before next MoabZu)

I did not know that, thanks for the information. I never noticed it occur. I'd love to be a fly in the wall at Isuzu and see what all that check does and what it does with the information.

I verified it was the A/C by to methods:
- Noise location (under hood)
- I don't have to wait 10-15 seconds, it happens within 5 seconds of turning the dial to defrost, and stops right after i turn it off defrost.
My most logical (though not guaranteed correct) thought is it's the A/C.

For me:
- Defogger = A/C on to help remove internal moisture.
- Defroster = A/C off to allow the air to be hotter and melt the frost/ice faster.
I can no longer control that.

As for heating up the front windows, some thoughts:
- Higher temp thermostat to raise coolant temp going into the heat exchanger
- Open up the heat exchanger and see if the coils are dirty/dusty on the outside
- Complete engine coolant flush with scale remover to make certain the coils inside the cabin heat exchanger aren't clogged up.
- Wire a cabin switch in for the A/C to defeat it from in the cab when you're defrosting.

For those of us without sweaty dogs in lower-humidity environments, a combo of heat and incoming fresh air usually does the trick. I'm just going to live with it now that I have understanding.

I want to stress again I'm not making a huge rant or refusing to buy an (actual) Isuzu vehicle again. It's just an unexpected surprise. Going with the "cars taking over" comment, add that "people are stupid and know to put in gas and that's about it." Isuzu most likely went with the crowd and assumed a light turning on and off without pushing the button would freak people out. I give them credit for maintaining the button, many USA cars did away with that years ago.