Technical start/charging problems

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Technical start/charging problems

davejonsie

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I have starting/charging problems.The car starts if I jump it but will immediately quit once I disconnect the jumper cables. The car is a 2012 Fiat 500 pop with a 1.4, standard transmission. Any thoughts on where to start looking. At the risk of stating the obvious, I have an alternator (or related) problem. Is the alternator protected electrically on this vehicle? Could something be popped? If not how do I verify it is actually the alternator itself. Thanks so much in advance for taking the time to help me with this problem
 
I have starting/charging problems.The car starts if I jump it but will immediately quit once I disconnect the jumper cables. The car is a 2012 Fiat 500 pop with a 1.4, standard transmission. Any thoughts on where to start looking. At the risk of stating the obvious, I have an alternator (or related) problem. Is the alternator protected electrically on this vehicle? Could something be popped? If not how do I verify it is actually the alternator itself. Thanks so much in advance for taking the time to help me with this problem

I'd suggest if the vehicle starts when jumper leads are connected but won't run without them the very first thing to do is change out the battery.
 
We could trouble shoot it with you but since it's under warranty call the dealer. The alt is Canbus controlled so there could be any number of factors causing your problems. You will need a new battery too, as the charging fault has killed it.

I'd suggest if the vehicle starts when jumper leads are connected but won't run without them the very first thing to do is change out the battery.

Not true, a vehicle without a battery at all will run just fine on the alternator. The battery is only there to start the car. In fact, an old diesel will run without a battery or alt.
 
Not true said:
By that token so will a steam engine...
wink.gif
A petrol engine might run without a battery, but will it run with a bad battery? When I had a battery in a previous vehicle die "on the job" so to speak, the engine just ran down and stopped. Jump-starting would get it going and it could be kept running at high revs when the leads were removed, but drop to idle and it'd stall immediately. It was a fun drive home...
 
Typically, a battery will still start a car with a shorted cell. The battery must be seriously dead to short out the alt. sufficiently for it's output voltage to drop below being able to run the ECU/ ignition.
 
Thanks for the replies, pretty sure it doesn't have a steam engine although I've been told the driver might.
I believe under normal conditions the car should be able to run without (or with a dead) a battery.
Couple of questions:
Does the alternator have protection? Some type of fuse. None is listed on the owners manual.
Can a shorted cell(s) in the battery short the alternator?
Both are good case scenarios.
Replacing the alternator is going to be a problem. Is is so buried, I can even see it. I think it is actually located between the piston and the connecting rod.
 
I believe under normal conditions the car should be able to run without (or with a dead) a battery.

Perhaps in the old days, but modern car electronics are much more complicated & some parts of the system might simply shut down if the ECU doesn't detect a battery voltage within limits.

If you try to run the car with a failure in any of the principal electrical components (battery, alternator, ECU & IBS on S/S cars), then

a) the car might not run at all

and, worse,

b) you risk frying one or more of the rest.

Personally I wouldn't for one moment even consider using jumper cables on any modern car. One good transient spike as you are attaching/removing a cable & you could ruin thousands of $$$$ of electronics in an instant.
 
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I have two batteries which perform jumper duty for our fleetof cars. Here they are jumpstarting the wifes Legacy which has sat for justover a year :)

Being a Subaru it started and ran no problems :)
 

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One good transient spike as you are attaching/removing a cable & you could ruin thousands of $$$$ of electronics in an instant.

I believe this to be a myth. Likely senario is a fried ECU results in a car that won't crank, someone tries to jump start it and it doesn't work, blames the dead ECU on the jump start.

When you fit a new battery you're zapping your ECU from 0-13 volts instantly. When you're jumping a battery you're going from 8ish to 13, the transient spike is much smaller, and the old battery can act as a capacitor/buffer for inrush currents.

I briefly worked for main dealer roadside assist. All we used were regular jumper cables, not even those fancy "ECU safe" ones. The only cars we didn't touch were Ferraris and Lambos. Porsches and Maseratti's were OK though.
 
I have starting/charging problems.The car starts if I jump it but will immediately quit once I disconnect the jumper cables. The car is a 2012 Fiat 500 pop with a 1.4, standard transmission. Any thoughts on where to start looking. At the risk of stating the obvious, I have an alternator (or related) problem. Is the alternator protected electrically on this vehicle? Could something be popped? If not how do I verify it is actually the alternator itself. Thanks so much in advance for taking the time to help me with this problem


I had the same problem with my USA 2012 just a few weeks ago and replacing the battery fixed the problem. It was strange to me that there was no warning, just stopped at the store and the car would not start. jumping only got me home, but jumping would not start the car at home. changed out the battery and no problems since.


maybe all the experts here need to stop trying to be the top dog, expert, and help the post starter with their problem.
 
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