Battery / Alternator Issue...

[Charles89]

Ok, here's my issue. Yesteday when I was working on my car, I left my car in ignition to play music (should have put it into ACC) thinking my battery is good enough to last a while..

4 hours later, the music just died and I realised I've just drained my battery... So I had to get the car jump started. It starts with no problems at all and end up going for a 5-10mins drive to dinner. But after dinner, battery went flat again.. So I used a jumper pack to start the car.

Once started, I went for a 1-2hr cruise, and what I notice is, everytime I put my highbeam on or even fog lights, it would drain so much battery that it will restart my headunit and also stalls the car...

And today, I started the car a few times, a couple of times it took a few secs to start, but didn't have to use the jumper pack, but the highbeam problem is still there...

But what I don't get is, my battery was 100% healthy before I drained it out and never had any of those issues above, which I'm guessing my alternator was fine before that...

So what can cause these issues? And the battery should have been fully charged by a 1-2hr drive right? And is it true that once the battery is drained, it won't hold charge again?..

Any help would be appreciated!

[Duncan]

Yes, unfortunately a perfectly healthy wet style battery can die from a single flattening (is that even a word?). I'd start by swapping in a different battery.

[t_revz]

Once started, I went for a 1-2hr cruise, and what I notice is, everytime I put my highbeam on or even fog lights, it would drain so much battery that it will restart my headunit and also stalls the car...

And today, I started the car a few times, a couple of times it took a few secs to start, but didn't have to use the jumper pack, but the highbeam problem is still there...

So what can cause these issues? And the battery should have been fully charged by a 1-2hr drive right? And is it true that once the battery is drained, it won't hold charge again?..

1-2hrs should be fully charged. after 10-15 mins should have enough to be able to restart the engine without assistance,

not true about flat battery not being able to be recharged. was prob down to 7-8v when the headunit turned off. that story comes from batteries that go flat and are left for a period of time which causes chemicals to change in the battery.

batt terminals arent loose from where you clipped jump leads on? maybe you twisted them a little causing them to come off.

need a multimeter to compare voltage at battery and alternator to see if its not charging correctly anymore or if not getting to the battery anymore.

could potentialy be the battery or alternator from having to work harder than normal charging back up too but i wouldnt buy anythnig until you test it

[erik]

chuck a automatic battery charger on it until it floats

[Charles89]

1-2hrs should be fully charged. after 10-15 mins should have enough to be able to restart the engine without assistance,

not true about flat battery not being able to be recharged. was prob down to 7-8v when the headunit turned off. that story comes from batteries that go flat and are left for a period of time which causes chemicals to change in the battery.

batt terminals arent loose from where you clipped jump leads on? maybe you twisted them a little causing them to come off.

need a multimeter to compare voltage at battery and alternator to see if its not charging correctly anymore or if not getting to the battery anymore.

could potentialy be the battery or alternator from having to work harder than normal charging back up too but i wouldnt buy anythnig until you test it

The terminals are definitely not loose, but possibly a bit too dirty lol.

erik - yeah I might try that first and see what happens.

Just hoping I haven't killed my battery :S

[89CAL]

Check the water level inside the battery as well. And as above check your terminals. If everything was 100% before hand then I wouldnt expect the battery or alternator to be completely dead afterwards, especially the alternator

Just check everything, start at the battery and work your way to the alternator

[Charles89]

I just had a good look in the engine bay, checked all fuses and connections, they seem to be all good.

Then took the car for a drive, took a couple of seconds to start but still started, the voltage on my MFD was reading 14.5v or so, but when I use highbeam, the voltage drops to about 13v, headunit restarts, car almost stalls, then after I turn highbeam off, everything becomes normal again....

[mr031]

did you check the water in the battery?

Edited December 30, 2011 by mr031

[89CAL]

Hmmmm it shouldnt drop that much when turning the high beams on. I had to put a new battery in mine yesturday and thought the charging voltage was low so was turning lights on and off. It only dropped momentarily (only by 0.4v or so at the most) and then went back to its charging voltage.

Check the wiring for your high beams if its only when using the high beams it seems to cause the problems. 13v shouldnt cause anything to drop out either. Id expect that to happen more around 8v or so.

Somethings wrong there. Check your water level in your battery, and check your wiring, especially around your head lights

[Charles89]

Hmmm.. The battery is a maintainence free battery... So how can I check the water level?..

[89CAL]

Hmmm.... Does it have a window type thing with a colour indicator showing the condition of the battery? If it truly is maintenance free then you cant check the water level, what sort of battery is it?

[Missileman]

If it helps here are some voltage readings I took from the battery terminals earlier today...

R32 gtst auto

resting volts = 12.91

idle volts = 14.15

idle + headlights on = 14.03

idle + high beam on = 13.98

I went for 300km drive on Wednesday so the battery should have been well charged.

Cheers

Mike.

Edited December 30, 2011 by Missileman

[89CAL]

Cranking volts tell alot of the story, only one you missed out ^

Other then that, looks about right, not much variation is good.

[Missileman]

None around to turn the key for me

[Charles89]

Hmmm.... Does it have a window type thing with a colour indicator showing the condition of the battery? If it truly is maintenance free then you cant check the water level, what sort of battery is it?

There's no window, no nothing...

[Charles89]

Here's some readings that I took down just before.

When driving, my voltage is between 13.8 and 14.2.

When idling, it goes to about 13.8 with headlights on.

When driving, I tried high beaming, everything seems fine, no drop of voltage like before.

But when I was idling and tried high beam, voltage drops and car almost stalls.

So would it be my battery or alternator? I've lined up a optima yellow top for pick up tomorrow, so I hope it's not my alternator...

[89CAL]

Sounds like your alternator is working fine for the voltages while driving along. You can get your battery tested at an Auto Elec's shop using a carbon pile tester or whatever they use at that shop. Will tell you if the battery is stuffed or not.

what is your idle RPM? It seems a bit weird that it only has the issue when idling. I wouldnt assume that the alternator is spinning to slow at idle but if your RPM is really low, it might be a problem. Still not convinced though

so when your idling and turn the high beams on it stalls? or does it nearly stall? try sitting in neutral giving it a few revs and turning the high beams on, leave the revs up for a bit then let it to return to idle.

Just to see what happens, if its the sudden load at the low RPM or if its just not producing enough amps at that speed to charge the battery.

[Charles89]

I just picked up an Optima yellow top 750CCA from my friend today, he used it for like a year.

After I installed the yellow top, the same thing is still happening :S

And I idle at about 700?

So can this be the alternator?....

Are there any fuses I should be checking too?..

[Charles89]

Oh and also I just took a reading from the old battery, it is reading 12.66v...

That's a pretty healthy battery, isn't it?..

[89CAL]

Raise the idle up to 850rpm and see if it fixes the problem. 700rpm is a bit to low anyway