car batt. on its way out?

[Dy_]

mums car wouldnt start this morning. it was turning over slowly and wouldnt start. so i jump started it and it started, so i let it idle for about 15 minutes and now the car is starting fine [even after leaving it off for 15-20minutes]

does this mean the battery is on its way out?

[dsp26]

depends how much of the total charge it actually holds...can't really tell without taking the battery out and plugging it into a charger/conditioner.

but that scenario sounds sufficient if your mum doesn't listen to doof doof in her car:thumbsup:

[flipfire]

Check out the battery's health, if its fine then it might be your alternator.

[aaronng]

Check the water level in the battery and top up with distilled water. While the engine is running (give it say 1200-1500rpm), measure the voltage across the battery using a multimeter in DC mode. It should read about 14V. If it is close to 12V, then the alternator is weak/dying/retiring.

[Dy_]

battery water level is fine.
also did what you said aaron and its running at about 14.4 - 14.5 volts.

also noticing each start up is getting harder.

battery is dying then?

thanks everyone

[BluEG]

Alternator sounds fine,

Battery sounds like it is slowly going (CCA's low) + colder weather doesnt help

how old is the battery?

[Dy_]

Alternator sounds fine,

Battery sounds like it is slowly going (CCA's low) + colder weather doesnt help

how old is the battery?

mmm about 6 years old?

getting battery replaced after i finish uni lol.

all good thanks everyone.

[aaronng]

battery water level is fine.
also did what you said aaron and its running at about 14.4 - 14.5 volts.

also noticing each start up is getting harder.

battery is dying then?

thanks everyone

One more test is to keep the multimeter hooked up the battery, start the engine. If the voltage drops below 12V when the engine is starting, then the battery is on its way out.

[Dy_]

One more test is to keep the multimeter hooked up the battery, start the engine. If the voltage drops below 12V when the engine is starting, then the battery is on its way out.

hrmm how much below 12? the batts sitting at 12 while its not on.

thanks btw. learnt something new today. does the alternator test apply to most cars?

[aaronng]

hrmm how much below 12? the batts sitting at 12 while its not on.

thanks btw. learnt something new today. does the alternator test apply to most cars?

Yeah, it will sit on 12V when off, but as soon as you crank the engine, the voltage should drop. Just saw your post on it being 6 years old. That's a good lifespan you got there out of that battery. On our car, we had a sealed maintenance free battery which was not allowed to go flat at all, but it started dying on its own after 6.5 years.

Yes, you can test the alternator on most cars with a multimeter. Just be careful when hooking it up, because some alternators output a lot of current which can burn the fuse inside the multimeter. If that happens, just go to Jaycar and get another fuse.

[TheGoodDeal]

Go to
Mekong Auto Spares
42 Canley Vale Rd Canley Vale
They'll happy test it free for you anytime and they sell Battery too