When it’s hot (especially now that I’m in the Phoenix area), AC is on, and idling, the ABS/Coolant/Charge lights will fade on and off. Is this a common thing, or just a weird quirk of my car?

Stressed electrical system? Weak/failing alternator, maybe?

 

My first thought is the alternator and/or connections and grounds.

 

Thanks. That’s the direction I was looking at, and it’s nice to hear you though similar. I’ll check the alternator and connections! There’s a whine I need to track down under hood. I assumed it might be the vacuum pump but hopefully the alternator is the source.

More proof that this is a 28yo car, despite the mileage…meterage? 😄

 

Yep, all the idiot lights will come on if there's a low voltage issue. Easy to check and test with a multimeter.

Dale