My just bought - literally 2 days old to me - 04 MC SS - lost power this morning on my commute from work & slowly died out. I think just about every warning light in the system came on before all gauges & lights (even headlights, brakes, etc) went out & eventually the car died entirely. I coasted off the road, tried to restart to no avail (seemed like dead battery), called a friend & had him try to jump me. It worked, got me home but barely! Same issues after the jump. Know previous owner well, he mentioned issue that now seem like he had something draining the battery, said car wouldn't want to start if he let it sit for a couple days at a time. I can see the drain accounting for not starting, even an alternator for dying, but why all the weird electrical symptoms during the fail? Heard about BCM problems in these vehicles. Getting started on testing batt/alt & will update when I know, but seeing as i just bought the old gal a couple days ago, I'd love to have some more experienced insight before I start throwing more money down the drain. I've been waiting to have this car since I laid eyes on her brand spanking hot off the press in 2004, & now my dream comes true & she dies on me. Please, someone have me an easy answer. I'm def no car expert, could use the help. Thanks all.

 

Forgot to add, car was also very sluggish after jumping & when it was dying. If I gave it anymore than a smidge of pressure on the gas it would seem to want to stall, but idled okay while moving. Didn't die when I stopped in the driveway either. Sat there idling but then wouldn't start back up when I shut it off. Also, all power items dimmed & died out, including windows, locks, etc. Battery light came on last night for a minute, then went out & didn't come back on til it died on me entirely, along with Trac assist, airbag & service lights. Like I said in op, about every light in the dash had a warning but then slowly faded with the power. Seemed awful strange to me. Can see straight dying but all the extra system warnings? Seemed like a little more involved electrically then just a bad alt / battery. If I think of anything else I'll add it, this all happened at 6am after a 13hr night shift so I'm recalling as I go here. Lol

 

Sounds like a bad alternator, the reason all the light would come on is because the computer isn't getting proper voltage. Check the volts at the battery fully charged it should be between 12 and 12.5 volts, when it's running it should be around 13.5-14.5 volts. If the battery is less than 12 volts when sitting it could be because of the draw your taking about or a dead cell which would register around 10 volts. Good luck

 

The battery has now magically charged (while sitting all day, not running or being able to start). All lights & gauges seem to be working properly again, but now I have security light & it wouldn't turn over until I did the security bypass trick I read about here involving leaving the key on & trying in a few minutes. I don't know exact reading but my "car guy" tested battery & said it was good. It's new within the last year from previous owner. As I said, now the power seems to be back, even the voltage meter (I'm sure it has a name I don't know lol) in the dash is reading that it's got power now, the clock, dash, security & so on all seem to have reset but again, regained power without the alternator having run as I didn't start the car all day? I don't know much but that seemed off to me. Could that happen if it was dead this morning & now has power to start? I really can't afford to play musical chairs with expensive parts just to find they aren't the issue. Sorry for dissecting, just really need to narrow this down as just taking it for diagnostic testing will cost me more than my dignity is worth. Lolol I really appreciate the help!!
thanks so much for your input

 

Sounds like maybe a bad ground... Or connection.

 

So now I get in car, have full power (or enough to start engine anyway) & when I turn the key just to the On position it starts seeming to draw power a lot & erratically?! I can hear an audible "womp womp womp" & the lights on the dash brighten & dim with the noise. This is NOT on start, just ON, where I've been setting the ignition to get it to bypass the passlock. It seemed to work earlier today but now is making this scary noise & very quickly seems to be draining the power as when I let it go for a few seconds making the noise the lights go dim & die off quickly. I'm at a loss here. Won't start now either but to be honest, I'm afraid to turn the key any further at this point!!

 

Now is the time to check voltage. Let us know what it reads.Will need a volt meter but saves you from blowing parts at this time.

 

I'll have to wait for my friend to bring me a meter tomorrow morning so I'll leave it alone for tonight. I appreciate all the suggestions! Keep ya posted tom about what voltage readout is. Hopefully nothing new by then symptom-wise but I'll be saying my Hail Mary's just in case lol
Just so I'm clear, I should test while it's making the noise specifically? Basically you're saying I want to hook up the meter while off then see where it is when I turn the key & So on?
Sorry, as I said, I'm no mechanic, but I can't afford one either so I'll learn as fast as I can!!
Thanks so much!!!

 

Now when you're having issues would be ideal. Checking when the car is off would tell you if the battery is good or not , don't care about age because a plate (cell) can break at any time. Good luck

 

Same thing happened to me in a 1995 Grand Am a few years back, alternator went and the lights faded out one by one, codes popped up, and it finally died. Put in a new alternator, jumped the battery and it was good as new. Those were your original symptoms so sounds like that is what it is, like Jeff said use the volt meter to confirm if you are getting higher voltage once it starts.