Technical Stop Start Story

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Technical Stop Start Story

Mick F

Happy Chappy
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Nov 2, 2014
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Tamar Valley, Cornwall
Hi guys.
Just thought I’d put a new thread on here to combine the bits and bobs about my struggles with Stop/Start on our Sept 2011 61 plate 500TA Lounge.

We bought her - we call her Rosa because she’s Pasodole Red - only four weeks ago with less than 14,000miles on the clock. Within a few days, it was obvious that the S/S system wasn't good, and I joined this forum in an effort to find what was wrong. The S/S actually worked, but only stopped for 20secs max, and sometimes much less, though was almost adequate with zero drain like the DLR lights off and the ACC off.

I was prepared to take Rosa back to the dealer where we bought her, or to a Fiat dealer to be sorted, but I wanted to be in possession of the full facts before I went anywhere.

The almost unanimous advice was that the battery was shot, but maybe it could be resurrected with a good battery charger. I bought a Ctek and charged Rosa’s battery, but nothing changed. I had the battery checked by a professional and he said the battery was good, meanwhile I charged the battery again and again and again and again and again ............ but none of it helped. 20secs or maybe 30secs was all Rosa could manage.

On advice from the forum, I disconnected the small connector on the -ve terminal on the battery in an effort to reset the electronic system. I did this, and went for a drive, but the S/S stopped working entirely!

I searched the forum yet again, and found that you should never charge the battery whilst still connected, so I disconnected the -ve terminal and charged the battery again, then we went out for a long drive this evening - shopping and stuff - and meanwhile the S/S system not only worked, but worked well. We managed 2mins or more on many an occasion ...... and that was with the headlights on! :)

I have learned three things:
1. The battery is fundamental to the S/S system working correctly.
2. The battery needs a full charge, but the alternator isn’t enough to do it if there’s a problem.
3. When the battery is charged using a battery charger, it needs to be done whilst the battery is disconnected from the car.

So thank you everybody. The S/S system works now, and it's all because of the battery not being charged correctly.

Regards to all from Cornwall,
Mick and Rosa.
 
Pretty much.......

Most people and dealers just aren't capable of sorting this and in truth it's not really that difficult.
 
Hi guys.
Just thought I’d put a new thread on here to combine the bits and bobs about my struggles with Stop/Start on our Sept 2011 61 plate 500TA Lounge.

We bought her - we call her Rosa because she’s Pasodole Red - only four weeks ago with less than 14,000miles on the clock. Within a few days, it was obvious that the S/S system wasn't good, and I joined this forum in an effort to find what was wrong. The S/S actually worked, but only stopped for 20secs max, and sometimes much less, though was almost adequate with zero drain like the DLR lights off and the ACC off.

I was prepared to take Rosa back to the dealer where we bought her, or to a Fiat dealer to be sorted, but I wanted to be in possession of the full facts before I went anywhere.

The almost unanimous advice was that the battery was shot, but maybe it could be resurrected with a good battery charger. I bought a Ctek and charged Rosa’s battery, but nothing changed. I had the battery checked by a professional and he said the battery was good, meanwhile I charged the battery again and again and again and again and again ............ but none of it helped. 20secs or maybe 30secs was all Rosa could manage.

On advice from the forum, I disconnected the small connector on the -ve terminal on the battery in an effort to reset the electronic system. I did this, and went for a drive, but the S/S stopped working entirely!

I searched the forum yet again, and found that you should never charge the battery whilst still connected, so I disconnected the -ve terminal and charged the battery again, then we went out for a long drive this evening - shopping and stuff - and meanwhile the S/S system not only worked, but worked well. We managed 2mins or more on many an occasion ...... and that was with the headlights on! :)

I have learned three things:
1. The battery is fundamental to the S/S system working correctly.
2. The battery needs a full charge, but the alternator isn’t enough to do it if there’s a problem.
3. When the battery is charged using a battery charger, it needs to be done whilst the battery is disconnected from the car.

So thank you everybody. The S/S system works now, and it's all because of the battery not being charged correctly.

Regards to all from Cornwall,
Mick and Rosa.

Great Mick! Now you only have to decide if the saving in fuel from S/S is worth worth all that bother.;)

I'm still not sure - but my attitude is that I paid for it so I want it to work.

Cheers.
 
Based on data collected here:

https://www.fiatforum.com/500/342685-some-interesting-data-collected.html?p=3407737

My commute wastes 1litre /100km on idling, or 0.5l if adjusted for a TA.

Fair point. My commute however is off-peak each way with an average of four to five stops and mostly in 70-80kmh zones so I daresay the saving is slim. Nonetheless I keep the S/S on - every little helps, eh? Which reminds me; today's refuelling day (every second Sat.) and I've got to vote...
 
I don't think stop start is especially aimed at saving fuel. It is more aimed at lowering cars pumping out emissions when stationary and the engine is not required.

I don't know for sure but I would imagine stopping and restarting is less fuel efficient?

I am not green by any stretch of the imagination but I would guess every little bit has to help??????
 
I don't think stop start is especially aimed at saving fuel. It is more aimed at lowering cars pumping out emissions when stationary and the engine is not required.

I don't know for sure but I would imagine stopping and restarting is less fuel efficient?

I am not green by any stretch of the imagination but I would guess every little bit has to help??????

Well, whether it's intended to use less fuel or produce fewer emissions - a corollary of the former - the effect is the same.

When I bought my 500 I hadn't seen a brochure (they were supposedly in short supply) and I didn't even know it came with S/S, that's how important is was. I didn't know it was there till I got home and started reading the manual.
 
Don't want to rain on your parade. But, we had same story with our S/S from new, car now 32 months old. Did a battery charge with everything disconnected a few weeks ago. S/S worked flawlessly for about a week, then back to its useless self once again. Not really bothered as plan to get rid soon, and as its the wife's car it is her problem (that sounds bad). What I meant is, it does not bother her, she finds it a pain when it does occasionally work because it then refuses to start again.
 
Don't want to rain on your parade............
That's ok! :)

I'm under no illusions about this. It worked yesterday, it may work today, but tomorrow is another day.

It may yet need a new battery, but as I said, the professional chappy at ATS say's it's ok. Maybe Mr Fiat may say something similar if I took it to them, or maybe they would say the battery is bad. I really don't know, but I thought I'd share my tale so far with the forum.

All I do know, is that after charging up whilst disconnected, it worked. :)

My fingers are crossed.
Mick.
 
FWIW, I always charge with the battery connected and S/S always works afterwards.
 
Yes, I know.
I also know you had problems, and yours was sorted by the temporary disconnection of the small plug on the -ve terminal. I tried it, but S/S stopped working at all. This situation was entirely ok, but I believe if something is SUPPOSED to work, it should work.

By trawling through the many threads about batteries, I found a post by JR saying the batteries should always be charged disconnected. I also remember a post by someone saying that the battery should be bench charged out of the car. I just disconnected the earth cable and charged it in situ, and from then on, S/S worked as designed.

Maybe a co-incedence?
Maybe eventually after charging half a dozen times, it worked?
Maybe the battery isn't holding a decent charge and when we go out later today, it'll be back to a 20sec thing?

I really don't know.

Scratches head ......
Mick.
 
Y
Maybe a co-incedence?
Maybe eventually after charging half a dozen times, it worked?
Maybe the battery isn't holding a decent charge and when we go out later today, it'll be back to a 20sec thing?

I really don't know.

Scratches head ......

Who knows? Unless you can reliably reproduce a problem by taking a known, specific set of actions, it's impossible to say for sure either what caused the problem in the first place, or what cured it.

Whatever, I'm pleased your efforts have got it working properly and I hope it remains so for a long time.

That said, and whether S/S is working or not, a car with a 3yr old battery, even one that tests as serviceable, is going to use more fuel than it would if the battery were new, and I'd certainly change it out at the first sign of any further issues.

It's a pity S/S batteries are so expensive, and wear so fast; IIRC someone 'in the know' once posted that power losses due to battery self discharge exceeded the gains from the S/S system once the battery was about six months old.
 
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How interesting!
Six months, and the battery costs more in fuel than it's worth.
A very thought-provoking statement.

The other day, after I disconnected the small plug on the -ve terminal, the S/S stopped working entirely, and it was a very liberating experience. Mrs Mick F is getting over a bout of siatica and doesn't want to drive, but she's adamant that when she gets a turn in the new car, she won't want S/S at all and hates the idea of it.

The trip out today was a success with the S/S, insomuch that on the few occasions we had to stop for junctions, it worked faultlessly for the required stopped time. Later, we purposefully stopped and timed the S/S and it went to just a tad over two minutes - DLR lights on.

Later still, we were stationary at a junction for nearly three minutes, however the car re-started before we needed it to.

Although it's actually working quite well, it ain't no substitute for turning the ignition key off, then re-starting as and when you want. Do it like that, and the car can be off for a week or more, not just two minutes! :)

S/S is only any good if the car would stop for as long as necessary.

Still not contacted Fiat ........ or our warranty company to see if the battery is covered. If it is they'll want a certificate from Fiat to say it's only fit for recycling. Meanwhile, I think I'm staring in the face of £100 for new battery.
Seems such a waste of money.

Thanks guys,
Mick.
 
Out today, and S/S was still absolutely ok.

Thinking about the possible history of our Rosa, we are the second owner, and she was owned and driven by a lady in the Torbay area. We think she had her on a lease from Fiat, and chopped her in for another.

Rosa, maybe was left alone for a while, and auctioned off. We do know for definite that the dealer we bought her from had bought her from an auction.

If she was left alone, we have no evidence to say for how long ............ perhaps it was weeks or months?

Maybe the battery decayed. Maybe when we she was auctioned, the people charged the battery. Maybe the dealer we bought her from charged the battery too. All we know, is that Rosa started and ran very well when we bought her and subsequently.

Maybe, by my regular charging and my disconnection and charging has re-set the whole system, but I can tell all our readers, that Rosa does her S/S very well indeed .............. and still does.

Maybe she only "stops" for 2mins or so, but that is a HUGE improvement from 10secs.

Moral of the story, is if you have a problem ............ charge the battery out of the car.

Regards to all,
Mick.
 
Charging the battery out of the car means reset (due to missing power supply) of batterysensor and ECU (involved in S&S management), what might cure the issue.
I did it on my TA several times by disconnecting battery and batterysensor , but days later the issue of restart after 10-30 seconds came back if cold outside.
 
I don't know.
All I did was read this forum and found info about charging the battery. There are lots of threads on the subject and there is conflicting advice here and there.

Also, if you read the handbook I have two versions :bang: and they give different advice! One says disconnect the -ve terminal, the other says to disconnect the lead crossing over the top of the battery by pressing the button.

I went for the "sensible" idea of disconnecting and isolating the battery as it appealed to my simple mind.

Whatever happened, I do not know. ECU reset? S/S reset?
Dunno at all. You tell me!

All I do know, is that S/S now works quite well ........ when before it didn't.

Thanks,
Mick.
 
The ecu doesn't get reset by disconnecting the battery


Its true, I mixed it up with BCU (BCM in German manual) - sorry.
I made lots of test, S&S behaves different if battery sensor is reset, if BCU is reset or both.
 
So after 10 months of flawless SS mine has thrown a wobbly too. Restarts after 10 or 15 secs or sometimes even less. It all started since the weather got cold pointing at a suspect battery. Experimented with turning heater off etc but made no difference. This morning was a lot warmer and no difference either. I disconnected battery sensor lead and reconnected - still no difference. I then disconnected and left off and went for a drive - no warning lights for about 3 minutes and then they came on. Have now reconnected and after about a 20 mile trip it hasent kicked in once so I presume it's relearning or whatever, seems if you disconnect you need to leave off for a few mins to have any effect. I measured voltage at battery terminals and it read 15.3V engine off and about 15.2 engine running which I would have thought was healthy enough. I'll wait and see what happens, I must admit it was quite refreshing driving around without the engine cutting out, if I had the choice I'd disable altogether, turning off at the switch is all very well but you have to put up with the annoying light. My car was a fresh build last January so wasent hanging around anywhere for months.
 
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