battery dead after a few minutes

Greenemachine

Registered
so today I had my hood open and my doors open for a few minutes... at the most 15-20 minutes.. when I went to start my car my battery didn't have enough juice to crank the car. its pretty warm about 90 so that might have something tod o with it, but I mean the battery is only a few months old, should I bring it back and get a new one.. or is it just that the heat and the lights on made it go dead?

Steve
 
RE: battery dead after a few minutes

I hope someone will correct me - but I didn't think Mark VIIIs would actually let that happen. I thought when the voltage got to the "danger" level for starting - it shut down the system and had to be reset with an "on/off" of the key switch.

Maybe it's bypassed - or your battery was already woofed before you opened the door.

Try the usual - cleaning of the terminals, etc.

You can also try the old "check the alternator" trick:
(NOTE: DON'T DO THIS UNTIL SOMEONE POSTS THAT IT'S OK TO DO IN A MARKVIII)
Get the car started.
Disconnect the battery (positive side)
If the car dies - the alternator's shot
If the car keeps running the battery's shot

Again - that was the OLD way to check "on the road". I don't know if it's a valid check with an electronic system however.
 
RE: battery dead after a few minutes

thanks it was the batt. the alt is also brand new too. I traded the old one and got a new battery.
 
RE: battery dead after a few minutes

I was going to say battery... as batterys age they lose reserve capacity, so if you run them every day they stay full up, but they drain down really quick.

The mark has a turn off lights/accessories after an hour when left on feature (or something like that), but your battery has to be good enough to get there in the first place.
 
RE: battery dead after a few minutes

so my car has stalled out the past few days cause of a dead battery. The batt is brand new. The alt is brand new. at idle with no accesories on the meter reads 12.80 volts. with everything turned on in my car the volts drop to 11.8-11.9 volts. if I dissconect the battery the car runs fine, the alt is working properlly. I was getting the door ajar message so I disconnected the alarm for now, thinking maybe thats the problem... but its not.
 
RE: battery dead after a few minutes

Testing your charging system quickly with a digital voltmeter (assuming charged battery):

1. Test battery voltage with engine off. Check at battery terminals at clean terminal or clamp, not the bolt or nut. Record voltage. This is your battery's standing voltage.

2. Start engine & run at 1500 RPM. With no other load (doors closed? Underhood light off? Auto headlights off?) - record voltage. Voltage should be higher but not by more than 2 volts. This is your charging voltage without load.

3. Turn on heater or AC to MAX along with turning on highbeam headlamps. Increase RPMs to 2000 RPM. Voltage should be a minimum of 0.5 volts above your standing battery voltage. This is your charging voltage with load.
 
Back
Top