Battery/Charging problem

[SHOoff89]

Ok, this one has me baffeled. My room-mate has a 98 SHO that has some sort of electrical problem. The car will out of nowhere just die, and not start up again, like the battery is completly discharged. We replaced the battery, and it didn't do it for about 3000 miles, but now it is doing it again. The lights will dim at night like it is not charging or the battery is heating up, and then after about 5 min it will brighten up again. The alt/batt light never comes on, and we tested it and it was charging fine. It is almost like it is overcharging (there was water by the service covers on the battery) and killing the battery.
Anyone have any clue on what this could be?

 

[venom]

Ensure that both connections at the megafuse (end of underhood fuse box) are tight. Check the grounds for the battery.. That's where I would start.

By saying die and not start do you mean that it stalls and immediatly won't crank? That really sounds like a ground to me, does anyhting else in the car light up (is there power everywhere else) when it won't start? There is also the engine grounding strap that might be able to cause this.


Scott Krietemeyer

 

[SHOtype]

Sorry it's happening to my SHO I accidently posted under my roommates login. After it stalls it will crank once or twice just like if you had a dead battery. Just before it dies the radio volume will turn way down, there is a quiet beep, and a couple of warning lights will come on but not always the same ones. this whole process takes anywhere from 10 sec. to a min.

 

[SHOZ123]

The alternator is probably bad and so is the battery now.

 

[SHOoff89]

But if it was the alt, wouldn't it throw up the dummy light letting you know that it is a charging problem? When we tested it, it came in at about 14volts. Too much maybe?

 

[stephen newberg]

If the alternator is putting out 14 volts or there abouts, that is what it is supposed to be doing, so it is likely not the alternator, but rather its results getting lost somewhere prior to the battery for some reason, grounding being most likely.

pax, smn

 

[SHOoff89]

Could this be related to his completely hyper-active transmission? maybe the computer? The damn thing shifts everytime you even barely touch the throttle when cruising. Is this common among Gen III tranny's?

 

[SHOGHOST]

Yes I would think it is some sort of grounding problem as well, and NOT the alternator if you have tested that and it is working.