Yes, what I meant was, if I change the battery, will the fact that it won't charge the battery affect it as I could drive to the garage 30 minutes away for them to change the alternator if I decide that I can do it myself as it does look a bit tricky in the videos I have watched.
Technical Fiat 500 1.2 Lounge alternator
- Thread starter jason1966
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Technical Fiat 500 1.2 Lounge alternator
A new battery will run the engine for at least an hour so it would get you to the garage(albeit loosing charge along the way!) also not the best way to treat a new battery by causing it deep discharge from the word go!.
Be better if you could beg borrow or steal an old battery thats still working & fully charge that, and use that to get to the garage so they can change the alternator, take the brand new battery along so that can be fitted with the alternator! so the systems set up for the journey home!.
Ok. You jump started the car and then checked the voltage with the jump battery still connected? If the alternator was working you should have seen at least 13 volts - more likely 13.5 to 14 volts - even with the engine running at idle ad certainly even if the revs were raised to as little as 2,000 rpm. The fact this didn't happen points to either the alternator being clapped out or a problem with the wiring. Wiring can differ but generally there will be a thicker wire which connects to the battery so should test out at battery voltage all the time and a thinner one which will only show battery voltage when the ignition switch is on - this smaller wire provides electricity to the field windings and varying this supply, via an ECU, is how output is controlled. As the AA guy diagnosed a "dead" alternator I think you can probably take him at his word. It's not a difficult thing to diagnose if you know what you're doing.
You say at one point you checked the battery and it read just 2.6 volts? If your existing battery is a stop start (most likely will have EFB or AGM on it somewhere) then letting it drop to this level will have almost certainly "killed" it. Old "wet" lead acid batteries were more tolerant of this sort of treatment but more modern batteries, the types mentioned above, really don't like it and "sulk" by going into a "deeply discharged" state from which it's very difficult to reawaken them. Regardless of the alternator performance, you almost certainly need a new battery.
Replacing both these components should sort the immediate problem but, if it were mine, I'd be checking for parasitic drain just in case something is robbing electricity while the car is standing. I do this by disconnecting the battery negative terminal and connecting in an ammeter between the terminal on the battery and the earth lead. I have a large current ammeter - 0 to 10 amps - with a 15 amp fuse in the lead just in case there's a dead short somewhere. Testing with an ammeter is potentially dangerous as an ammeter is basically introducing a dead short - ie, nil resistance - connection, so the potential to "blow things up" is great. If the 10 amp meter doesn't flicker then I stick my multimeter on in it's place and wouldn't expect to see more than 100 milliamps. If you're going to do this you need to open the bonnet, make sure everything is switched off, close the doors and give it a few minutes for all systems to power down. If your car has one of these infotainment screens then it may take a few minutes for everything to go dormant. I like to give it a quarter of an hour before doing a parasitic draw test.
This might interest you: https://www.continentalbattery.com/...mal amount of,quicker and shortening its life.
Fitting an old "wet" type battery to a stop start car is not recommended as it won't cope with the constant discharge/charge cycling and will almost certainly fail before it would in an older car without stop start. I suppose that if you could remember to always disable stop start when you start the car then maybe it would be ok as it's the repeated heavy current drain followed by recharging that does them in. It's very tempting because the old type batteries are quite a lot cheaper. @John202020 above mentioned Tayna, an excellent supplier of batteries as many on the forum will agree. Put your cars reg no into their product finder and you'll see what's recommended. If you know someone with a Halfords trade card that's another place to buy a good (Yuasa) battery at a good price, but only with the trade card.
Yes, it's a bit cramped, especially if the vehicle has an air con pump in the way! As @steveras57 says above, a new battery will almost certainly let you run the engine for 30 minutes at least to get to the garage but won't be an ideal way to treat a new battery - which may not actually be fully charged if it's sat on the shelf for a while before you bought it. If you do this ask the garage to put it on charge when you drop the car with them. You might like to consider putting the hand brake on at traffic lights etc, rather than holding on the footbrake with the brake lights using up electricity?
Edit. Most batteries now a days have a charge indicator "window" on the top of the battery. It's a wee transparent "thingy" you can look into and will display battery charge state by colour. The one we bought recently for my friend's Kia had a green indication when well charged turning black if charge state is low. It's a very crude indicator but I'd be checking this when I bought one and rejecting one which didn't indicate the charge to be "good" because if showing it's discharged you don't know how long it's been like that and a battery in a low state of charge will have been sulphating internally which is irreversible and reduces battery performance.
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12.8 is far more then you'd get normally from a battery without the engine running
Even a 100% charge AGM will struggle to get to that
Opinions differ!
Yeah you'd think so wouldn't you, especially in these days of super intelligent ECUs and whatnot.
But nope, mines not on either and it's not charging.
Greasytrucker
Established member
It’s probably just having a nap after what you’ve put the poor little car through recently!
I think this will depend on whether you have an ECU controlled alternator or one with an internal regulator. On the latter, which is probably what we have, the ignition light indicates that an electric current is flowing from the battery, through the ignition switch to the "exciter" (small) terminal on the back of the alternator and thence, via the regulator, to the field coils in the alternator. If the alternator is not generating electricity - as in when the engine isn't running - then the light will be on. However, if the alternator is turning and generating electricity then this will be "balancing" or "pushing back" against the electricity in the battery and so reducing the difference between battery voltage going one way and alternator voltage going the other way to charge the battery. Once the difference in this voltage falls below a certain value, maybe, say 4 volts, there won't be enough potential difference to light the bulb in the ignition warning light so it goes out. If the light doesn't go out the most common reason is that the alternator isn't charging. However, just because the light goes out doesn't necessarily mean the alternator is putting out enough to charge the battery, It only has to get somewhere near battery voltage to balance the system and cause the light to go out. Of course if the light never comes on, even with the ignition on and engine not running, then most likely the bulb is blown or there's a wire open circuit somewhere. However if you have a newer car, like my 2016 Ibiza or my new Scala, the ECU is totally in control and the dashboard lights may only illuminate for a bulb check when you first turn the ignition on and then extinguish only to relight if the ECU decides there's a problem. Makes fault finding very difficult for us oldies who are used to the way dashboard warning lights used to work.
Most annoyingly the oil warning lights now, on many cars, will only illuminate if the ECU detects a steady low oil pressure for a certain length of time. I really don't like this as it uses up critical run time when you could have switched the engine off and, maybe, saved the big ends/mains/etc, Also I don't like that the oil warning light now extinguishes after the bulb check takes place. This means that you can't watch the oil warning light as she fires up so don't know how long the oil pressure takes to build. Arrrgh! I hate all these "smart" features.
I'm going to get the 027 EFB Powerline Start Stop Car Battery 60Ah - this is going for about £70 delivered.
But now the alternator minefield. One site said Wai alternator 90 amp - surcharge free. part number waia7407 - this seemed a reasonable price with appropriate discounts and says it fits fiat 500 2014 1.2 lounge. But...How in god's name do I know this is correct as gsf site says it doesnt fit my car. They have a 70 amp which they say fits my fiat. (I can get 25% off) so about £100
wai alternator - 70 amp - surcharge free Part No: WAIA7698
Any experts on the purchasing of alternator?
But now the alternator minefield. One site said Wai alternator 90 amp - surcharge free. part number waia7407 - this seemed a reasonable price with appropriate discounts and says it fits fiat 500 2014 1.2 lounge. But...How in god's name do I know this is correct as gsf site says it doesnt fit my car. They have a 70 amp which they say fits my fiat. (I can get 25% off) so about £100
wai alternator - 70 amp - surcharge free Part No: WAIA7698
Any experts on the purchasing of alternator?
Being in a big city I'm spoilt for choice with 3 trade Factors near me to choose from. For just about all I need I simply walk in and give them the vehicle reg No. They look it up on their computer, talk to the warehouse out back and, usually within about 5 minutes a man appears at the warehouse door with it. Very very rarely do they get it wrong and if they do I can exchange it easily same day. If it's something I think might be difficult I take the old unit with me to compare on the spot. Prices at trade factors are usually not far off those on the net, and, every now and again, they actually beat them. These guys are selling to the garage trade mostly so daren't sell sub standard items and I find quality is generally very good. I rarely buy on the internet now and, as you buy more from your local factor and he gets to know you, you may find he gives you better discounts.
See my post #6 note the ss cars might come with a 120a version to provide enough charging and cars with ac may have a different design to the body?
So the 120 amp will be more powerful than the 70 amp which has to be good for the stop/start and the aircon. 10% off certainly makes it better value and a winner if it is 100% compatible?
Add up all the powers (Amps) of the heavy duty users on your car, then add a bit for contingency, and thats that is more or less the minimum size you need.
All of this should be accounted for when your regie number is fed into a search. Safest option is to fit the alternator specified for the vehicle. I don't understand why our OP is prevaricating over the different outputs? It's not as if you've fitted some accessory which is going to need a big increase in alternator output compared to the standard item?
However, I put the reg id and I was given a model then another site selling the same alternator said that wasn't suitable for my model. At this point, I defer to other posters knowledge.
Exactly why I like using a local supplier. Wrong part? just nip back down the road and in next to no time you've got the right part or your money back.
for sure the internet isnt always your best option! but people are becoming lazy and complacent!
I have to agree up to a point. But that might have something to do with often being able to get a better deal online, which thereby encourages people to buy online.
Most online sales are returnable these days, if you can be bothered.
Sellers are lazy, (or shady/ignorant) by not putting all the details of their products on view, but that's primarily because they don't know anything about the products they are selling anyway.
id say a good majority prey on making the returns process "difficult" and/or costly!
