Ke55 Battery Or Alternator?

[jara]

So for a few months there my charge light was coming on about 50% of the time i drove, i didnt realise that my battery was getting weaker though until i left on my lights and needed to jump start it. I charged my battery over-night with a wall charger and she was good again for about a week, then cranking was getting a little slower again and the charge light came on again. I cherged it over-night again even though the charger said the battery was fully charged. Next morning it was cranking nice and fast, but in the past week has gotten slower again, but the charge light has yet to come back.

 

anyway, what do you guys think the problem is? the fan belt is not loose

 

just don't want to spend a few hundred on a battery or alternator then find out i needed the other

 

cheers

 

i don't know if this matters but:

CCA - 530

CA - 650

Edited September 6, 2012 by jara

[ke70dave]

So for a few months there my charge light was coming on about 50% of the time i drove

 

This should ring alarm bells.

[Dust03]

I'd prob say battery, best bet is to start the car and check the voltage a cross the battery with a multimeter, I'll try n check mine for ya today for comparison, mine did a similar thing when the battery went

[B.L.Z.BUB]

Take it to a battery shop or autobahn they'll do a free battery check.

[jara]

cheers guys,

 

I'll head on over to super-cheap and see how much a multimeter is, or see if they do checks

 

but when the charge light does come on, why isnt it on all the time?

Edited September 7, 2012 by jara

[altezzaclub]

Does the red light come on if you have the headlights and the wipers on at idle? Even if the battery was dead the charge light wouldn't come on if the alty was working.

 

The light is on when power flows out of the battery, and it goes out when power flows into the battery. So if you see that light on when you're driving then the alternator or the regulator is not working.

 

The alty may not be charging enough to charge the battery up, so slowly you are losing battery storage until you top it up with a 240V charger. Then the battery is full again and lasts another week of being partially charged.

 

Get the alty charge rate checked and the battery storage capacity. The alty is not hard to pull apart, check the diodes, the brushes and the bearings and re-assemble, so get a diagnosis done but tackle the work yourself.

 

but when the charge light does come on, why isnt it on all the time?

 

Depends on the loading in the electrical system at the time. If the alty is only 50% efficient, it will charge enough to keep the light off when you're not using the CD player, the wipers, the headlights, its not raining, or whatever reason. Pull 150watts out and then the battery has to supply it and the light comes on. One diode of the 6 might have failed.

Edited September 7, 2012 by altezzaclub

[ke70dave]

have a read up on how charging systems work.

 

the charge light is connected one side to batter positiver terminal, the other side is on the alterantor.

 

if the alternator is charging, both the positive terminal and the alternator will have the same electrical potential = light does not come on - happy days.

 

If the alternator isnt charging properly, the positive terminal will have a higher potential than the alternator, and thus the light will glow. you will also flatten the battery.

 

and like altezza club sais, different load on the electrical system (llights, cd, wipers etc) will change weather the alternator can keep up or not, which is why i reckon you got the light on half the time.

 

if you don't know what you are doing, take it to an auto electrician and he will give you a diagnosis in about 5mins.

 

At first the alternator will sort of work, and the battery will flatten slowly, over time the alternator will get progressively worse and the battery will flatten quicker after you charge it up.

[jara]

well the charge light has definitely been on while driving, but i thiiiiink it mainly comes on when i'm at the lights. I'll ring around and get a diagnosis then, that way i'll know for sure. I wanted to avoid auto electritians though, about $100 an hour.

 

thanks guys.

[ke70dave]

well if you want to learn its very simple.

 

buy a multi meter - $10-$15.

 

put it on volts DC

 

and measure the voltage when the engine is off, and when the engine is on.

 

off it should be around 12 or so, on it should be between 13 and 14.

 

if its not higher when its on, alternator is stuffed.

 

if it is 13-14v, then get your battery checked.

[jara]

okie dokie, well i might aswell do that first, i'll pick one up at supercheap on the way back from getting the missus in a few minutes.

i'll report later today

 

the help i get from here is always great, cheers

[Bowler]

Alternator...Brushes on the regulator have gone. Classic case of it too.

 

I've had those same symptoms on one of my old cars - and both times, it was the regulator brushes. if its an external regulator, then won't be too hard to change (say 20 minutes). otherwise, you might need to see an auto elec, or get your hands on a new(er) alternator.

 

For the record, the symptoms where that the light came one for 5 min, then off, then on again intermittently. Battery was fine too. what happens, is that the regulator brushes come in and out of contact with the stator. You will find that the car will run without a battery connected, so long as the alternator is working too.

 

(SCA do free charging system/battery checks too - with printouts. takes 5 minutes. worth is for the piece of mind)

Edited September 7, 2012 by Bowler

[jara]

Well, i'll head down to supercheap again for that battery and charger check.

 

but for my own benifit, how do i use this? haha, just bought it and don't have a clue how i'd simply test the voltage coming off of my battery

 

http://www.supercheapauto.com.au/online-store/products/Stanley-Multimeter-Digital-Pocket.aspx?pid=9441#Description

[oldie]

plug the leads into the sockets,red positive black negative,turn the dial to the section that has the V with a straight line above it,this means DC voltage,then in that section,choose the 20 location,then put the red lead on the positive side of the battery and black on the negative side,read what voltage the dial says,then start the car and repeat the process,read the dial,your answers will be as those above have said,if when car is running you have around 13/14 volts its your battery at fault,if it remains at the pre start voltage then your alty is at fault,this is basic,think its right,hope it helps.

Edited September 7, 2012 by oldie

[jara]

there is no 20 bit in the section that has a V with a line.... do you mean the 20 that is at about 10 o'clock?

 

I put it on the BATT 9V option, it said 13.43 when car was off and 14.68 when on. but this seems like the wrong setting

 

also, supercheap's test reckons there is nothing wrong with the batter or alternator.... and the battery is at 69%, but apparently that's fine

[ke70dave]

yes the "20" at 10 oclock.

 

and just above it there is a V with a line above it.

 

don't use that 9v one.