New alternator. Is the battery the problem?
Discussion
My battery has been going flat intermittently for a few months. I got a new battery a couple of months ago but recently it's been happening more and more, to the point where, if left overnight, it will need a jump start in the morning.
I got a mechanic out and he told me the issue was the alternator, so I got a new one installed. The next day I had exactly the same issue. I've since done tests to check for parasitic draw but there isn't any. The mechanic advised that it must be the battery (having been worn out by the alternator issues and regular jump starts). I took it back to Halfords this morning and they tested it and told me the battery was in perfect health. Eventually they did agree to replace it, but I'm now concerned there is still an issue but I'm at a loss to what it would be! Any ideas if could still have been the battery or what else it could be?
Context:
Honda Civic 2005
The car will start if it's been driven within a few hours, but not typically if left overnight.
If it won't start it seems completely dead, where the central locking doesn't even work
When needing a jump start, it will need to be left charging for a few minutes before I can turn the engine on.
When it starts it does so straight away, with no odd sounds.
No other electrical issues detected.
Any help would be much appreciated!
I got a mechanic out and he told me the issue was the alternator, so I got a new one installed. The next day I had exactly the same issue. I've since done tests to check for parasitic draw but there isn't any. The mechanic advised that it must be the battery (having been worn out by the alternator issues and regular jump starts). I took it back to Halfords this morning and they tested it and told me the battery was in perfect health. Eventually they did agree to replace it, but I'm now concerned there is still an issue but I'm at a loss to what it would be! Any ideas if could still have been the battery or what else it could be?
Context:
Honda Civic 2005
The car will start if it's been driven within a few hours, but not typically if left overnight.
If it won't start it seems completely dead, where the central locking doesn't even work
When needing a jump start, it will need to be left charging for a few minutes before I can turn the engine on.
When it starts it does so straight away, with no odd sounds.
No other electrical issues detected.
Any help would be much appreciated!
You mention nothing of your driving profile.
If you only do short journeys your alternator will never have the chance to fully charge the battery.
Bets bet would be to fully charge the battery overnight, then test it's charge with a multimeter (12.7 volts ideally) with the car not running & then again with the engine running (13.5 volts plus typically) and this will give you a better idea.
Then have a good look round & check all major terminals between engine/battery/chassis/starter/alternator are good/clean/tight & do it properly not just a quick look as a terminal not in perfect condition will absolutely cause this issue.
If you only do short journeys your alternator will never have the chance to fully charge the battery.
Bets bet would be to fully charge the battery overnight, then test it's charge with a multimeter (12.7 volts ideally) with the car not running & then again with the engine running (13.5 volts plus typically) and this will give you a better idea.
Then have a good look round & check all major terminals between engine/battery/chassis/starter/alternator are good/clean/tight & do it properly not just a quick look as a terminal not in perfect condition will absolutely cause this issue.
^^^^ What he said.
Start by fully charging the battery with a battery charger.
Jump starting & a driving will do little apart from leave your battery deeply discharged & possibly damaging your alternator.
Alternators are not intended to charge flat batteries.
www.optimabatteries.com/experience/blog/fact-alter...
Start by fully charging the battery with a battery charger.
Jump starting & a driving will do little apart from leave your battery deeply discharged & possibly damaging your alternator.
Alternators are not intended to charge flat batteries.
www.optimabatteries.com/experience/blog/fact-alter...
paintman said:
^^^^ What he said.
Start by fully charging the battery with a battery charger.
Jump starting & a driving will do little apart from leave your battery deeply discharged & possibly damaging your alternator.
Alternators are not intended to charge flat batteries.
www.optimabatteries.com/experience/blog/fact-alter...
very much this, also worth checking battery cables earths etc.Start by fully charging the battery with a battery charger.
Jump starting & a driving will do little apart from leave your battery deeply discharged & possibly damaging your alternator.
Alternators are not intended to charge flat batteries.
www.optimabatteries.com/experience/blog/fact-alter...
And one a lead acid battery has gone flat they are often toast
Thanks for the replies. I now have a brand new battery and alternator. I would expect the battery to already be fully charged from new?
Having initially been told that the problem was the alternator, then the battery and then getting it tested and told it was in perfect health, my concern is that the the car will start fine for a while and then run into the same issues.
I guess my question is, it is likely that the alternator and battery were the problem? And should it now not be fixed, what could it be? Sounds like it would be a wiring/connection issue somewhere.
Having initially been told that the problem was the alternator, then the battery and then getting it tested and told it was in perfect health, my concern is that the the car will start fine for a while and then run into the same issues.
I guess my question is, it is likely that the alternator and battery were the problem? And should it now not be fixed, what could it be? Sounds like it would be a wiring/connection issue somewhere.
MekkoGekko said:
Thanks for the replies. I now have a brand new battery and alternator. I would expect the battery to already be fully charged from new?
Having initially been told that the problem was the alternator, then the battery and then getting it tested and told it was in perfect health, my concern is that the the car will start fine for a while and then run into the same issues.
I guess my question is, it is likely that the alternator and battery were the problem? And should it now not be fixed, what could it be? Sounds like it would be a wiring/connection issue somewhere.
you would think that a new battery is charged, however not always, the battery you bought may have been sitting on a shelf for months, they dont hold a charge indefinably even with no load.Having initially been told that the problem was the alternator, then the battery and then getting it tested and told it was in perfect health, my concern is that the the car will start fine for a while and then run into the same issues.
I guess my question is, it is likely that the alternator and battery were the problem? And should it now not be fixed, what could it be? Sounds like it would be a wiring/connection issue somewhere.
A multi meter is your friend, and not expensive, but you do need to be able to understand what its telling you.
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