C5 "dead battery" -- not quite

Following might explain a few of the electrical "mysteries" that get posted here from time to time.

Stopped at the market after my Sunday "desert romp." Came out and no electricity--nada. Opened the door with the key, then called AAA and got a jump. On the way home, the dash lights & HUD flickered off when I'd hit a pot hole. Voltage was all over the place, varying from 13 to over 15.

Back in the garage it started OK. After supper, tried to start it and move it to the barn for the week, "dead" again. Battery was putting out >12 volts with no load. Any load dropped it to zero but the green "tell-tale" showed battery was OK. Suspected the battery cable. It was OK.

Found a replacement battery (thank you PepBoys). When I pulled the old battery, found that the positive terminal had been severely overtorqued. (Don't know if this happened at BG or maybe at the original dealer if these cars are shipped with the batt disconnected.) Sufficient "wrench" broke the whole case around the positive terminal, exposing an old torsion crack in the lead stud inside the battery case. It had been oxidizing for years. Battery itself was in great shape.

Since I bought the car last year I've had strange dimming and brightening of lights at night (looked like poor voltage regulation.)

Went ahead and commuted with the new battery on Monday and Tuesday. No voltage regulation symptoms.

-- PJ '89 Hookercar '02 e-blu coupe

Reply to
PJ
Loading thread data ...

There was a recall on bad batteries and they went so far as to put a diaper, absorbent pad, under the batteries to catch the leaking acid. It leaks down on the mess of wires and becomes an $800 problem from a $12 battery. Just a little problem but they went to a top post on the C6 after 30+ years of side posts.

Reply to
Dad

That's interesting. There was some acid leaking out of the cavity where the positive terminal had been. Spill was only a few drops and that cleaned up easily with some baking soda. Don't know if the recall applied to the 2002s--if so, the original owner and I both missed it.

Thanks for the info--will keep an eye on the replacement (also an AC-Delco).

-- PJ '89 Hookercar '02 e-blu coupe

Reply to
PJ

There was a battery recall a few years ago...I forget who the mfg was but SEARS was giving away replacement batteries with no questions asked..after all their defective leaking battery had most likely caused several hundred bucks of damage to your car so they new you were not in the mood to argue over a $60 battery.

The batteries were sold under several brand names...none of which I can rember other than SEARS.( I got mine replaced by them )

Reply to
Maddog

Sorry to hear about your battery problems. We have all been there!

The dimming is normal. The next time you are stopped at a light with lights on what the refection in the bumper of the car in front. While watching lower the window, hit the brake light and you will see the best of GM engineering.

Reply to
aRKay

The BEST mod for the C5 is to ditch the crapy Delco AGM battery. I have had NO battery issues since changing to the Wall Mart Everstart. The good thing about the Everstart is Wall Mart is everywhere and they are open 7 days each week

Reply to
aRKay

Important point is that, regardless of brand, internal battery damage and acid leaks can result from overtorque of the terminal screws. I agree with the C6 solution that Dad pointed out--the top terminals, although bulky are electrically and mechanically superior. Reacting torque with a current carrying component, molded from lead, was dumb engineering--don't know who to blame for that SAE standard--however it did start in the '80s when electrical demands weren't as challenging as they are today.

I wouldn't leap to fault GM engineering on the load and grounding distribution in the C5--at least in the '02 with it's two load centers. Last year I dumped a leased G35X and that car had load distribution, grounding and voltage stability issues far worse than any in my C5. I wouldn't look to Renault-Nissan engineering as a template for progress.

-- PJ '89 Hookercar '02 e-blu coupe

Reply to
PJ

I think the problem started when GM reduced the thickness of the battery cable lugs that connect to the side posts. Since the newer lug is so much thinner, in effect, the terminal/bolt is too long and bottoms out in the molded battery post. After a while, the lead post begins to separate because of the stress causing first a leak, and later a totally broken terminal post.

I have a 99 Vette. One night, after I had refueled, the total electrical system was dead as could be. I opened the hood, and jiggled the battery cables to see if they might be lose. I was totally shocked when the positive cable totally disconnected from the battery. When replacing the battery, I first ground down the bolts about 1/16 of inch and haven't had any problems since.

FastFreddy

Reply to
FastFreddie

MotorsForum website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.