[Guest]

I through in a new alternator last week I thought my battery was good but I dont think it holds a very high charge today I started it about 3 times throughout the day and it didnt sound like it wanted to hit but it just turned over, my volt meter says im getting 12 when its the ign is in medium lock position, when driving it's USUALLY at 14, sometimes it trinkles down..... I'll probably get the batt. tested this week... any thoughts? Thanks.....

 

[Corey872]

Those numbers sound pretty good. 14V cruising, maybe drop to 12.5-13 stopped at a light? I think open circuit voltage for a fully charged battery is around 12.5V. But it is going to be hard to tell how much capacity your battery has with just the volt meter.

Sometimes I have turned the headlights on high beam, step on the brake, have radio on, and turn heater blower to full (all with car not running)...this draws a good amount of current, then check the battery voltage after 20-30 seconds of that. Again, not a great method, but the battery should recover pretty quickly to 12+V

 

[Guest]

the other day when i was working i left the key turned in ign. and it couldnt have been more than 5-10 minutes at the most, and it wouldnt start i had to jump it. the starter and alt. are new.... it seems ok from the volt meter but eh, i just dont know yet. Ill try turned some stuff on and see if your method works with this. Any other ideas would be great! Thanks....

 

[rthlc]

Sounds to me like a new battery is in order.

 

[Corey872]

Sounds to me like a new battery is in order.

I second the motion. If a few minutes of key on, engine off drained the battery it sounds like you just don't have any capacity left. Charge numbers look good (14V) so the alternator/regulator is doing it's job.

 

[Peter F.]

Battery here too.

A test I have done before is to disable the ignition and then crank it for 15 to 30 seconds. There should be no noticable loss of cranking power. If the cranking falls off then the battery is bad. It sounds like you have a 1-hit battery. If you don't get it going the first hit on the key you're not getting it going.

Peter