Battery or alternator problem? help?

[mark089]

car died aus day at warwick shops, jumped it drove it home (2 mins away), charged battery drove it like 2 mins n it died again so jumped it drove it home then 5 hours later cranked it over and it started first shot
was going to get new battery but starting to think its the alternator not giving battery enough charge??
sorry bout dumb question just want to know definate

[joshg123]

Get a multimeter, your wanting to see about 13.5v at the battery when the cars running.

[matty12]

^^^^and check from engine off to engine running,should be a noticable diffeance between the two.if there is alt should be good,otherwise get a capacity discharge test done on the battery,most auto electrician/mechanics can do,shouldnt get below 10volts from memory.

[pshrdeta]

if cranking car with high beams on battery shouldnt drop below 10.5 volts really

as for charge rate we go for 13.8-14.2 though if its low give it a rev it may be charging at a higher current so needs more rpm to maintain the desired voltage

[DoctorDubb]

Have you checked that the battery has enough (distilled) water in it? My battery wouldnt charge (even though on a charger it said it was 'full') and i found this to be the culprit.

But it does sound more like an alternator problem if it dies while your driving as it shouldnt be using your battery then.

[mark089]

cheers for the imput guys was alternator as i thought all fixed now thanks again for all information came in handy