When new vehicle sales were down, thanks to God for jumper cables, those kept our sales up. Certainly a variable to the damage done depending on the state of charge of your vehicle's battery. It has to be discharged first and charge up in the reverse direction.
The first thing to go would be the main diodes in your alternator, they would be forward biased, hopefully they would short out to protect the rest of the electronics, but typically will burn open. For reverse polarity protection, the simplest cure would be to design a circuit that would operate at 0.6 volts less with just a single diode in series, most can take several hundred volts reverse voltage with no damage, it just simply will not conduct.
But they don't do this, instead add a parallel diode to the electronics, if it is there at all, that will conduct if reverse polarity is applied. But typically too small, what it is suppose to do with reverse polarity is to conduct blowing a series fuse, but the diode may short out first due to excessive current.
Another really stupid idea enforce by idiot marketing, those stupid basterds are in charge, is always hot. With a vehicle like my 88 Supra the radio and most of the electronics is off when the ignition switch is off, so reverse polarity wouldn't hurt anything. Cruze does have an ignition relay that is off if the ignition switch is off, and this should be the case whenever jumper cables are installed. Do you really give a dam that you can turn your Cruze radio on when the ignition key is in your pocket?
Remote entry always has to be hot, and do you really give a dam if your dome light stays on for a few seconds after you close and lock the doors? Marketing seems to think so, again a bunch of stupid bastards. But do it their way or no longer have a job. Anti[thief, in my opinion completely worthless always has to be always hot.
If your head lamps were left on, the BCM should have turned them off, but facing another more newly created problem, the battery. Basically on the excuse to save weight, instead of putting ten pounds of crap in a ten pound package, doing that today in a five pound package. Self discharge has become a major problem the way they are designing crap today. Also your BCM is always hot.
And of course the ignition switch in the Cruze is not a switch, it just fires commands to the BCM. And your radio is not a radio, its a computer that depends on code stored in flashram to operate. 0.75 volts on the wrong pin can erase all the code in the five computer systems in the Cruze. 04 Cavalier sure wasn't this way.
And unfortunately you cannot go to your computer and download the code to reflash your ram, have to go to your dealer. I would try this first.
Really do not like how they are making vehicles today, but not only GM, they are all doing this now.
