Ok, battery is fully charged, I've cleaned the terminals with a wire brush and electric cleaner. When there is no load on the car all functions are normal. As soon as I turn the key to ON, I hear a strange buzzing noise from the passenger footwell and everything goes DEAD. Obviously there is a short-circuit somewhere, but has anyone ever run into this before? Luckily it died in my driveway....

 

Well,,,,,If you truly had a SHORT CIRCUIT, you would see either a blown fuse OR smoke followed by fire and then charred plastic stuff. It's more than likely a bad electrical connection OR you supposedly good battery isn't good.

I strongly recommend completely removing the battery and go have it load tested to make sure it can can handle starting loads. When you get it back home, install it and correctly torque the battery terminals down to 11 FT/Lbs of TQ. That way the cable terminals are making good contact with the battery terminals. If you can move the battery cable terminal by hand,,,it's way too loose.

A bad connection between the battery terminal and battery cables will cause that exact problem.

BC

 

Ok I'll try this, but there is no way the battery was find one second and bad the next. I literally pulled into the driveway, shut it off and went to restart it and this happened, I had been driving it around for the whole day. Are there grounds or something in the passenger compartment under the carpet? I heard noises from there.

 

Yes batteries fail like that all the time, have it load tested!

 

It is very likely you were driving around in your car with all the power you needed provided by your alternator (Which it is suppose to do)

However your battery has been going bad over time, and not accepting a charge. Now it doesn't meet the minimum charge to start your car.

It is also possible that it is not the battery, but you can't (Shouldn't is probably a better word) really move on to the next step of electrical diagnostic without knowing you have a battery that is 100% good.

How old is your battery? Where I come from in Arizona, it is so dang hot we have to change out batteries every two years. If you don't feel like taking yours out and going to Autozone/Checker Auto Parts/Krager for a free battery check, do you have another car with a similar battery you can swap TEMPORARILY?

 

Batteries can and do fail outright. Had a 2 month old brand new RED TOP! One day it worked 100% the next day it was totally DEAD (no voltage at all). Had to have the car towed to the dealer. (Car was under warranty) Thought it couldn't be the damn battery! Well,,,they charged me an hours worth of labor and told me to get another RED TOP Boy was I pissed.

The battery is a mysterious black box. You cant open it up and examine the internal parts. (well you can,,,ONCE and its really messy )

Unless you have it properly tested using the correct test equipment (load tester and recovery rate tested) the battery is always going to be under suspect.

Now that Ive said that, once you tell us that you have had the battery correctly tested, I will tell you that you need to check the POS and neg battery cables for correct tightness and condition. You need to follow them down to the starter and engine block and the POS cables to the fuse junction boxes and make sure the connections are clean and tight.

The weird noises that you were hearing were relay/s being unhappy due to very low voltages. They make a humming and sometimes squealing noise when they cant make adequate coil closing contact. That condition is NOT conducive to long relay life.

There are conditions that cause the bolts that secure the battery cables not to be able to apply the proper contact on the battery. See if you can wiggle either battery cable by hand. if you can, thats the issue. They MUST be properly torqued to 11 ft/lbs (1997-2003 C5) to make proper contact.

BC

 

That's exactly how my battery went, I pulled into a gas station, filled up and battery dead.........very possible expecially if it's the original battery. Test the battery as Bill noted!

 

WOW! Ok I guess you learn something new everyday. Turned out to be the battery, crazy! I've never seen one die instantly like that. Thanks guys!!!!!

 

Batteries do go open circuit internally from one crank to the next. Enough current to light up the dash, until you try to crank it. Ask me how I know ..... LOL!!

RonJ ...

 

Found this using the search.
Almost exact same scenario playing out with me right now.
Pulled into the driveway. Shut down to move another car. Came back out and it tried to turn over, then, nothing. Just the clicking relays.
The battery is on the charger right now. I'll be taking it in shortly.
I'll let you know how it goes.
Rob

 

This condition must be contagious or something, because I just had my car go completely dead (40 miles from home) with relays clicking & a whopping 7 volts when I put a meter on it. Sure glad Pontiac Grand Prix batteries are similar (sideposts). It was a little late at night to be buying one & I was now sitting in a dark parking lot. Thought I might have to sleep in my car that night.

 

Good luck FASTOYZ.
I don't have a voltmeter to check.
It's just sitting out in the driveway looking pathetic.
I'll get it checked and replaced (probably) tomorrow.
I'll actually be happy if it's just the battery.

 

Had the battery checked this morning. 12.47 volts.
Bought a new one and the car fired right up.
Hopefully, this will last me another 5 years.
Rob