Hi all, just taken ownership of a 500 lounge 1.2 engine, 12 plate with 27k on the clock. Drove it 15miles back from seller today and been out few other short journeys. One thing i have noticed is the start stop not kicking in. I'd have thought that would come on once warm, it does on my diesel golf. Didn't have aircon on in journey. The seller did mention a new battery had been fitted to the car not long ago so was wondering if it could be related or do the fiats need a while to warm up before this technology functions?
Technical Start Stop
- Thread starter greggp
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Technical Start Stop
Do you have owners manual as I think the S/S feature can be turned Off.
Is the battery that was fitted the correct one ( I reason I ask is that the correct one for a S/S 500 is super expensive and if they were thinking about selling when battery was fitted then may be cheaper option fitted!) as this may have an influence
Paul m.
Is the battery that was fitted the correct one ( I reason I ask is that the correct one for a S/S 500 is super expensive and if they were thinking about selling when battery was fitted then may be cheaper option fitted!) as this may have an influence
Paul m.
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Hi, yes have a manual. There is a button on the dashboard next to rear heated screen where you can deactive s/s a button illuminates on speedo when deactivated. Are you suggesting you can turn it off permanently as didn't think this would be allowed due to the £30 road tax which I guess is so cheap and to do with S/S
Thaidai
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Would agree, check it's the correct battery fitted....
Thaidai
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That looks like the correct battery to me. The start/stop only works when the battery is in peak condition. It may have been standing a while and lost some of it's charge, so if you have a battery charger give it a boost or use the car for a while regularly and see if the start/stop starts to work...
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They are very fussy things, I’ve had cars that they never work in. Very temperamental. The battery could need a good bench charge, or replacing or one of the many factors that decide whether it kicks in or not. Personally I hate it and always turn it off.
Agree it looks like the 'proper' battery but unless it is in tip top condition then the S/S won't kick in, like others have mentioned there are quite a few perameters that have to be satisfied for the S/S to function, ie engine temp, accessories being used, charge rate etc.
You might find that it will kick in all of a sudden when the car is used sometime in the future and it might come as a bit of a shock!
Paul m.
You might find that it will kick in all of a sudden when the car is used sometime in the future and it might come as a bit of a shock!
Paul m.
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The Stop/Start system on these is at best dimwitted and cheap.
What everyone is telling you is true, it will only work with the battery in A1 condition, with little load on the electrical and HVAC systems and the engine at operating temp.
Unfortunately the system isn't really suitable to keep the battery in A1 condition, is self defeating.
It's nothing more than a switch/sensor attached to the normal starting system with just a heavier duty battery and cables.
Energy used from the battery has to be replaced, to do this the alternator has to work harder and use more fuel.
So every time the engine stops and restarts, the engine uses more fuel to work the alternator to recharge the battery, though this takes time.
Normal batteries don't really like being worked like this, so in most cases (but not this one) more advanced batteries (AGM) are used to cope with this.
So you end up with a battery that's good enough to start the car on the key, but the sensor on the battery won't let it self stop as it detects the battery isn't quite up to a restart, so the alternator is constantly working to try and recharge it to the required level.
The fix, you'd think would be to perhaps fit a bigger, stronger battery, but this would now cause the alternator more problems as it would have to work even harder to try and recharge the thing.
So what about fitting a more powerful alternator to charge the bigger battery? That will require more fuel to turn the feckin' thing!
Like I wrote, the system Fiat use is self defeating, it's just a fudge to report lower emissions. You'd probably be better off switching it off altogether.
Better systems utilise wasted energy or use other, free means to perform the restart, these tend to work better and actually save more fuel as you are not having to recharge the battery after the restart.
Mazda's Styactiv system stops the engine with a cylinder on the compression stroke, then fires that plug to perform a restart.
Other systems use energy captured from engine braking via a hybrid alternator, this is stored in capacitors which is then used to turn the alternator to bump the engine back to life rather than the starter motor, as it's a quicker restart and more efficient and doesn't detract from the main battery.
I've a diesel Citroen e-HDi with the later system and it works every time once the engine is warmed up. It actually switches the engine off before it's at a standstill (under 8mph for the auto/13mph for the manual), so you coast the last few yards saving even more.
It restarts in 400 milli seconds very smoothly and it actually saves fuel.
I've worked out my trip to work and back is around 8% more efficient with it on than off.
My Panda didn't make a difference as it never knocked off!
My Abarth hasn't a stop start system, then again with a Monza exhaust on it, why would you want is sitting there silent at the lights?
What everyone is telling you is true, it will only work with the battery in A1 condition, with little load on the electrical and HVAC systems and the engine at operating temp.
Unfortunately the system isn't really suitable to keep the battery in A1 condition, is self defeating.
It's nothing more than a switch/sensor attached to the normal starting system with just a heavier duty battery and cables.
Energy used from the battery has to be replaced, to do this the alternator has to work harder and use more fuel.
So every time the engine stops and restarts, the engine uses more fuel to work the alternator to recharge the battery, though this takes time.
Normal batteries don't really like being worked like this, so in most cases (but not this one) more advanced batteries (AGM) are used to cope with this.
So you end up with a battery that's good enough to start the car on the key, but the sensor on the battery won't let it self stop as it detects the battery isn't quite up to a restart, so the alternator is constantly working to try and recharge it to the required level.
The fix, you'd think would be to perhaps fit a bigger, stronger battery, but this would now cause the alternator more problems as it would have to work even harder to try and recharge the thing.
So what about fitting a more powerful alternator to charge the bigger battery? That will require more fuel to turn the feckin' thing!
Like I wrote, the system Fiat use is self defeating, it's just a fudge to report lower emissions. You'd probably be better off switching it off altogether.
Better systems utilise wasted energy or use other, free means to perform the restart, these tend to work better and actually save more fuel as you are not having to recharge the battery after the restart.
Mazda's Styactiv system stops the engine with a cylinder on the compression stroke, then fires that plug to perform a restart.
Other systems use energy captured from engine braking via a hybrid alternator, this is stored in capacitors which is then used to turn the alternator to bump the engine back to life rather than the starter motor, as it's a quicker restart and more efficient and doesn't detract from the main battery.
I've a diesel Citroen e-HDi with the later system and it works every time once the engine is warmed up. It actually switches the engine off before it's at a standstill (under 8mph for the auto/13mph for the manual), so you coast the last few yards saving even more.
It restarts in 400 milli seconds very smoothly and it actually saves fuel.
I've worked out my trip to work and back is around 8% more efficient with it on than off.
My Panda didn't make a difference as it never knocked off!
My Abarth hasn't a stop start system, then again with a Monza exhaust on it, why would you want is sitting there silent at the lights?
^that^.
I wrote something similar not long after S/S became standard on the 500.
I've read elsewhere that the system actually uses more fuel than it saves once the battery is more than three months old.
roberteajohnston
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I have 2017 500x 1.4 Multiair purchased secondhand in October. My stop/start has never worked properly, the dealer has fitted a new control unit and checked the battery power. It now doesn’t work at all, but as the conditions of winter driving may preclude proper working I have decided to wait for a few months before getting them to try again. Had a Ford Focus which had the same problem, dealer couldn’t fix it. Before the Fiat I had a Honda Civic and it worked every time.
I had a 12 plate 500 and you could NOT turn S/S off. The two we have had since allow it to be turned off. I have it turned off all the time - don't really see the point of it to be honest - extra wear on Starter Motor and Battery for what? My cynical view is that they are fitted to get the CO2 levels down in the none real world tests used by ALL car makers.
We all know that as cars get long in the tooth then they do not start on the button like when new, so in a few years time imagine being at the lights behind a couple of aging SS that just chug away for a while before you get chance to pull away.
Paul m.
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Yeah, and a big ass starter motor and huge regenerative alternator....
You have a 120Ah alternator and a 80Ah starter motor. It takes ~1 second to start a healthy engine, so provided you brake for a few seconds to stop, you've got plenty of free power for a restart.
I use a 120Ah battery. No problems, in fact my car has apparently unbelievable economy.
The stock 120A alternator is about twice as big as it would be on a non S/S car. It's fine running a 120Ah battery if you wish.
You mean like the Fiat system?
Hybrid starter/ alternators are new tech that no one had in production a decade ago. Other than a bit of weight and complexity saving, there's no real advantage to integrating the two.
Fiat's is a decade old system, it's not going to be as good as the latest tech is it? I've still got 55mpg three tank average.
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People always love the 'seatbelts cost more lives than they save' chestnut, applied to whatever new tech there is.
Do the maths. It takes 80A for 1 second to start a warm engine.
That's 1.3Ah
1litre of petrol has a GSE of 8.87kWh. Let's say 30% ICE efficiency and 40% alt efficiency.
We need roughly 11Ah GSE to restart our engine, or 0.00124 litres.
If idling uses 1- 0.6l/hr, then that makes the break even period roughly five to ten seconds. I manually stop cars without S/S (ie zero re-engineering) and it always saves fuel - 10% for my city driving.
One thing's for sure, I wouldn't be getting up to 60mpg city from a 2+ ton van if I just left the engine idling. 42mpg three tank average.
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You'll find Hybrid alternators aren't new, no where near new.
Citroen E-HDi system was launched over 10 years ago in 2008 and I would guess as it's Citroen, they weren't the first to fit one.
GM used a belted hybrid alternator in 2007.
Mazda's Skyactiv is almost as old, dating from 2010.
I believe the 1st gen Prius used it's electric motor/generator (M/G) to start the ICE as far back as 2001, it never had a normal starter motor and never used a normal battery to start at all.
When did Fiat offer stop start as standard on the 500?
Without wanting to sound pedantic, this sort of technology really is from a bygone decade and is much more efficient than large lead acid batteries and heavier alternators.
That's not my opinion, the proof is in all those real mpg figures dotted around the internet.
A 2.0 petrol Mazda built in the same decade as a 1.2 Fiat share almost identical mpg figures, the 1.8 Mazda actually beats the Fiat.
They aren't using newer tech, they are using better tech.
Citroen E-HDi system was launched over 10 years ago in 2008 and I would guess as it's Citroen, they weren't the first to fit one.
GM used a belted hybrid alternator in 2007.
Mazda's Skyactiv is almost as old, dating from 2010.
I believe the 1st gen Prius used it's electric motor/generator (M/G) to start the ICE as far back as 2001, it never had a normal starter motor and never used a normal battery to start at all.
When did Fiat offer stop start as standard on the 500?
Without wanting to sound pedantic, this sort of technology really is from a bygone decade and is much more efficient than large lead acid batteries and heavier alternators.
That's not my opinion, the proof is in all those real mpg figures dotted around the internet.
A 2.0 petrol Mazda built in the same decade as a 1.2 Fiat share almost identical mpg figures, the 1.8 Mazda actually beats the Fiat.
They aren't using newer tech, they are using better tech.
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As much as I hate Pb batteries (I've retrofitted older cars with LiFe and supercaps - not possible of course on new cars), there's not that much wrong with them.
Weight has no measurable impact on MPG. My old 1.6 Renault averaged 6.7 city over two years (16mph average speed) and on a really bad traffic day 9.7 with a 500kg+ trailer.
If you work that out that's 0.006l/100km per kg, worst case (comparing an 'average' to a 'worst ever' is already being unfair), and don't forget that includes rolling and aero drag (enclosed trailer). If you run that through a speed/ power calculator, you find that 0.006l can easily be eaten up just by the aerodynamic drag (which went up 1100 counts) and rolling res.
My new Trafic weighs 2.1 tons (like I said, best city commute I had was 60mpg), has much the same system as FIAT, large smart alt, beefed up conventional starter, only real difference is the AGM battery. It works flawlessly, is super fast to restart (ie I can't possibly beat it- I've tried) and a few reviews have said it's the best they've ever used. No mild hybrid or supercaps just a big battery, big regenerative alt and big starter.
The fact that no one seems to have followed Mazda down the Skyactive route suggests it maybe more gimmick (or dead end) than real tech. I know a couple of people with Mazda 3's and for all that's gone into them they really aren't that impressive. They start quick enough, but no more than my modified Proton.
The idea of integrating starter and alt might not be anything new, but at a guess less than 1% of new cars sold today are fitted with them. For them to be worthwhile they need to be coupled with a 48v system. Very few such cars are on sale at this time.
Weight has no measurable impact on MPG. My old 1.6 Renault averaged 6.7 city over two years (16mph average speed) and on a really bad traffic day 9.7 with a 500kg+ trailer.
If you work that out that's 0.006l/100km per kg, worst case (comparing an 'average' to a 'worst ever' is already being unfair), and don't forget that includes rolling and aero drag (enclosed trailer). If you run that through a speed/ power calculator, you find that 0.006l can easily be eaten up just by the aerodynamic drag (which went up 1100 counts) and rolling res.
My new Trafic weighs 2.1 tons (like I said, best city commute I had was 60mpg), has much the same system as FIAT, large smart alt, beefed up conventional starter, only real difference is the AGM battery. It works flawlessly, is super fast to restart (ie I can't possibly beat it- I've tried) and a few reviews have said it's the best they've ever used. No mild hybrid or supercaps just a big battery, big regenerative alt and big starter.
The fact that no one seems to have followed Mazda down the Skyactive route suggests it maybe more gimmick (or dead end) than real tech. I know a couple of people with Mazda 3's and for all that's gone into them they really aren't that impressive. They start quick enough, but no more than my modified Proton.
The idea of integrating starter and alt might not be anything new, but at a guess less than 1% of new cars sold today are fitted with them. For them to be worthwhile they need to be coupled with a 48v system. Very few such cars are on sale at this time.
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