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I had mine changed by the dealer in late 2009, I normally run with Xenon headlights on during the day (yes, I'm one of them..).
 

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Shouldn't make a difference, once the cars started your alternator is providing the power, not the battery.
 

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Shouldn't make a difference, once the cars started your alternator is providing the power, not the battery.
mmmmh you reckon? I always thought you do put some strain on the battery regarless..

Mine was changed by the dealer (late 2006 car), but again I didn't have any direct signs it needed a new one, and it was in the phase when they were trying to sort issues out (by changing everything that isn't welded to the chassis!)..
 

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i bought my brera 2.4 when it was 3 years old and 16k on the clock,had it 2 days and the battery packed up so dealer paid for a new one. the aa guy said he had had few 159's battery fail and unlike most batterys you get no warning that there about to go they just stop working:rolleyes:
 

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Normally you get a fair few ecu faults flagging up before hand! Common ones are vdc failure and the like.
 

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4-5 years in the UK, depends on usage, I just sold a 156 with an 8 year old battery - it could lie for 2 weeks and still start (albeit it turned over a bit slow) but daily driving it was fine.
 
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2-3 years max on all my Alfas from new.


Checking levels and topping up where needed every 6-12 months will extend this.
 

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Shouldn't make a difference, once the cars started your alternator is providing the power, not the battery.
No, the alternator provides charge to the battery. You cannot run a car with a knackered battery and a good alternator.
 

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My 07 Brera is still on original battery. As long as alternator is fully functional, it will keep charging the battery.
:tut: You cannot charge a knackered battery.
 

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No, the alternator provides charge to the battery. You cannot run a car with a knackered battery and a good alternator.
A car will happily run with an alternator and no battery once the engine has started. Battery life is dependant on a large number of variables. Lead acid batteries like to remain charged. The common cause of early failure is if they are left with low charge for a period of time.

With regular use (and hence charge from the alternator) and provided there is not a high parasitic drain when the car is 'off' you should be able to get many years from a modern battery.

James
 

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A car will happily run with an alternator and no battery once the engine has started.
I so disagree. Surely you need the battery for voltage regulation?

It may run for a while, but an engine will run for a while with no coolant. I wouldn't recommend it though.
 

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I so disagree. Surely you need the battery for voltage regulation?
Nope.

The battery will provide no regulation. Once the engine is running it is just another load on the alternator. The batteries voltage is typically 12.5 volts. Alternators run between 13-14 volts.

I once had to do a 140 mile trip running on the alternator with a completely dead battery. Was not enough power for the interior light with the engine off. Once the engine was running (after a bump start) the car was perfectly happy.

James
 

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It might run (for a while) but far from happily.

An alternator is an AC generator, or Alternating Current generator. You cannot use it to generate power without a battery as it needs to be 'loaded' to work. You CAN use it to generate electricity though, as the unit has diodes built in, and a bridging rectifier to keep the energy flow in one direction and convert it to DC. The job of the regulator (in a car) is to regulate the voltage to meet the needs of the battery and keep the volts at approx 14.4. Increase the load on the battery, and the regulator draws greater load from the alternator to keep up the voltage. You can start a car, remove the battery, and drive around for a while but eventually the alternator will fail. An alternator cannot 'sustainably' generate power without a battery as it uses the back load to generate the electromagnetic field needed in place of the magnets in a generator.

However, if you didn't have any other power drain, ie no lights, stereo, fans etc and kept the revs to about 2000 rpm, it could last quite a while but in the real world? You need a battery.

Anyhow, I would suggest that after 3 years use of a battery it's suck it and see time, after 5 years you are gambling!
 

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look, none of us are saying that you can and indeed SHOULD run a car without a battery, it's foolish to say the least..

It's like saying, my engine won't run, but i could get it half a mile down the street if i put it in gear, and used the starter motor to turn the wheels.

But the whole point is that the battery is there in the main, to give you the cranking amps to start the engine in the morning. Once the car is up and running, and the alternator is dumping out it's nominal 14 volts, the battery is charging, and the car is being run at the same time from the alternator.

Yes your quite right, when you turn lights/fans/etc etc on, your putting a greater electrical load on the system, and the battery takes up some of that slack before the alternator picks it back up again...but once a car is running, a battery is operating in more of a capacitor type capacity, than you thinking that electricity flows in, to then flow straight out again to the spark plugs etc etc rest of the car.

It's a parallel power system, not a serial one.

Either way, 'turning things on' in your car, ISN'T going to shorten the life of the battery, miscare and incorrect usage will. As well as extreme temperature changes.
 
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