hi.....have been tryin today to get to the bottom of my battery drain problem,after 1 week without use im finding my battery flat when i come to use the car.i've checked the usual....condition of battery and if the alternator is outputting correct voltage....i even phoned the tracker installer to get his input but assures me it won't be the tracker as it won't pull enough amps to cause the problem,its a my05 wrx......has anyone had simular problem or knows of any common faults?.........also anyone know the specified cca of battery required.

 

This is a common problem, the battery doesn't last long. I'm on battery number 4. Alternator doesn't charge unless you got sidelights or something switched on, probably find your battery is knackered.

 

have had load test done on battery and alternator is puttin out 14 volts

 

bump

 

It will put out 14 volts under load, that is why it is called a smart alternator. If driving with no lights, wipers or heaters etc on then it doesn't charge the battery unless you take your foot off the gas and are rolling up to a junction for instance. I can monitor this using my Scangauge. I would say your battery is stuffed and it's not holding a charge properly. Do a search on here and you'll see plenty of people suffered same problem. Varta D47 or equivalent is fitment. I've had OEM, Bosch and now on my second Optima Redtop. My mate with an 02 STI has had same problem and is now using the Varta from Advanced Battery Supplies @ £70.00

 

Firstly. Is the battery properly charged?

The below table is the open circuit voltage after being stood overnight: If the battery is below 12.4volts it will suffer permanent damaged from suphation if left like this for long periods.



Just jump-starting the car and useing the alternator to charge it will NEVER fully charge the battery (unless you drive around for 24hours non stop). If you ever suffer a flat battery the car must always be put on a mains battery charger - how long depends on the charger used and battery size/state of charge.

Some "dumb" chargers if left on too long will damage the battery. Some automatic charger can undercharge the battery. However a 3/4/5 stage intelligent charger is simply a case of waiting for the green light (this takes two days on my Golf...due its huge 90Ah battery). Charging info can be found here: http://jgdarden.com/batteryfaq/carfaq9.htm#types


Finally, the tracker; ignore the call centre lady. She knows squat about automotive electrics. Fact; a tracker with a faulty internal battery will drain your vehicle's battery. I've worked and disgnosed on cars suffering from this fault and after disconnecting the tracker's power supply the problem was rectified.

Either way, if its an old generation tracker, the maximum the car will stand unused is about fithteen to twenty days. If the car is used for short journeys, this will be less.

 

This man talks sense. I have had this same problem and was getting fed up of changing batteries. After having gone through two Yuasa 60 amp batteries in as many months I got the car checked out. Both the batteries were knacked, and would not hold charge. There was no drain. My problem was too many short journeys and a battery that wasn't high enough rated. Fortunately I had an old Exide battery knocking about that was okay. Put that in and now I make sure the car is driven more (at least one half hour journey too). So far so good. The only other option is to disconnect the battery in between use.

 

The problem is if you have a discharged battery - even though it can still start the engine it is getting damaged through sulphation, resulting in a loss of capacity. And will ultimately kill the battery.

I've lost count how many batteries I've once killed through my own ignorance. Nowadays I just pop the voltmeter on it every odd week before starting the car to make sure its above 12.5V. If its low, I stick it on charge overnight.

Not killed a battery since, be it on my cars or bikes.

 

thanx for the advise guys

 

I have a similar problem with my own car (05 STi) and there is no fault with either the battery or alternator.
I only do short journeys and they are sometimes only twice a week. So when I need to use it I use my smart charger, which is brilliant but only really a short term solution.
I suspect the tracker to be the culprit and would appreciate, by PM if nescassary, advice on its exact location so that I can disconnect it. Prehaps the OP could try this also.

 

As my bugeye is now the second car, I use a smart charger every other weekend leaving it overnight to top the battery up. It maintains the battery at about 13.2v when connected so is not an issue for the electrics on the car. Just be thankful you don't have a Renault Scenic, oops that is now my first car, this used to be my Dad's and when the battery went flat you could not unlock the door with the central locking. Renault had thought about this occurance and have fitted a key lock with a key in the remote key fob, unfortunately when the converted the car to right hand drive they left the key lock on the passenger door. So you need to be quite skinny to get between the garage wall and the car.

PS, thanks for reminding me, neeed to run the scooby for 10 minutes tomorrow.

 

Sorry to bring this up again but my battery keeps dying on me and im fed up with it. If i get another new battery and drive about with my sidelights on all the time will this help keep charge in the battery? I never really use anything apart from the radio in the car

 

It will help, using my Scangauge I can see 12.? volts without them but 14.? with them on. TBH I've not been driving with mine on as I have the fan set to Auto and does the trick instead once engine up to 50 degrees as it doesn't kick in until then. I'm now also using my car daily whereas before I wasn't. The radio might not be enough, anything that draws a bit of power eg wipers, heater, electric back window, lights on will kick the alternator into life.
Another thing I noticed, if using throttle with no power being drawn it stays at 12v, if you take foot off like coming up to a junction it kicks into life....smart alternator designed to charge when just it thinks your engine doesn't need that little extra bit of power?????

 

Sidelights, or heater/blower fan on all the time, at No1.

Not killed a battery yet

 

it might sound silly but i brought 2 new batteries for my scoob and 2 alternators..... and my battery kept dying check when you turn the key that your battery light comes on because i was told if that light dont come on it stops the charge and drains it!! i changed the 13p bulb and good as new £350quid for a 13p bulb