Technical Start-Stop system operation

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Technical Start-Stop system operation

Turned my S/S on for today's outing and it worked exactly to spec - staying off at one point for over two minutes! To be fair the battery was on the charger for several days prior and I really need to leave it off the charger for a while and test it further to confirm. Then I can turn it off again...🙃
 
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Don't know about Fiat, but on other makes the outside temperature is a factor too.
And in Oz it is spring time now isn't it?

gr J
Practically summer actually. I've never seen any reference to ambient temperature related to the FIAT system but Melbourne's climate is pretty mild anyhow; 0 degrees is rare and it never snows of course. My rear subframe doesn't have even surface rust! Actually it's an ideal place to own a 500, especially a cabrio.

I won't connect the charger till it's had another run - that should indicate if the 7-year-old EFB has lost its edge.🙃
 
Actually it's an ideal place to own a 500, especially a cabrio.
Is there not a risk of UV damage if parked outside frequently? Even in the UK, we're seeing some quite serious cases of clearcoat delamination on cars >10 years old, especially red ones.
 
Is there not a risk of UV damage if parked outside frequently? Even in the UK, we're seeing some quite serious cases of clearcoat delamination on cars >10 years old, especially red ones.
Good point JR, it may not be ideal for the car. I probably should have made that a caveat but in my case it's a minimal risk. Remember mine is quite coddled, being garaged when at home, and in the hotter months I carry a half-cover to protect the fabric roof and interior when it's unavoidable to park in the sun. In that scenario, black of course can literally burn a careless hand! I also have a full cover for the rare occasions I have to leave it outside;
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Nonetheless it's still an ideal place to drive a 500 Cabrio... My roof is open for nine out of ten trips. 🙃

PS: It may not snow but it sure can hail!!😉
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Is there not a risk of UV damage if parked outside frequently? Even in the UK, we're seeing some quite serious cases of clearcoat delamination on cars >10 years old, especially red ones.
My roof is the only original paint on my car she is 13 now and it’s fine …. Although she gets waxed!! She also gets special shampoo.. maybe white cars come off a bit easier!!?
 
I won't connect the charger till it's had another run - that should indicate if the 7-year-old EFB has lost its edge.
So, that happened today - after five days sitting idle, and without charging, the S/S performed exactly as it should! Very happy with that - now I can turn if off again... 🙃
 
My start stop has stopped working again . It lasted 6ays! Checking MES everything was good and 96% battery. I did the neutral signal learn again and it it then worked again. So I am now thinking the neutral sensor or what activates it is not quite aligned or is not secured properly. According to e-learn the sensor is fitted below the gear lever on drivers side. I will need to remove the surround trunking etc below the gear stick to get access. 2nd hand sensors are available on eBay or club500 in case the sensor is faulty. Looks like the gear knob and gaitor may need to come off too. I'll report back when i have had a close look at the sensor.
 
My start stop has stopped working again . It lasted 6ays! Checking MES everything was good and 96% battery. I did the neutral signal learn again and it it then worked again. So I am now thinking the neutral sensor or what activates it is not quite aligned or is not secured properly. According to e-learn the sensor is fitted below the gear lever on drivers side. I will need to remove the surround trunking etc below the gear stick to get access. 2nd hand sensors are available on eBay or club500 in case the sensor is faulty. Looks like the gear knob and gaitor may need to come off too. I'll report back when i have had a close look at the sensor.
when removing be careful with the snap ring that secures the gator to the housing its quite brittle and easy to break when removing some of the screws/torxs its helpful to have a stick magnet to stop them falling down behind the panels which is a real p,i.t.a :D (y)
 
So I am now thinking the neutral sensor or what activates it is not quite aligned or is not secured properly
I'd say this is quite likely too.

With mine, if it doesn't immediately stop the car on coming to rest, sometimes just giving the gear lever a slight wiggle about the neutral position will cause the S/S to kick in and kill the engine.
 
My roof is the only original paint on my car she is 13 now and it’s fine …. Although she gets waxed!! She also gets special shampoo.. maybe white cars come off a bit easier!!?
You only need to put a hand on a white car parked in scorching sun compared to getting burned on darker colours to understand how right you are. Even silver cars are much hotter. I can open the door and get in and close the door even on the hottest days with my white one it would kill you in the burgandy coloured one. In a pale blue car I actually baked some food I had bought for the weekend. Ive never forgotten the baked Granny Smiths apples that were a suprise find before setting off to drive home 250 miles one friday night. What a treat.
 
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You only need to put a hand on a white car parked in scorching sun compared to getting burned on darker colours to understand how right you are. Even silver cars are much hotter. I can open the door and get in and close the door even on the hottest days with my white one it would kill you in the mrgandy coloured one. In a pale blue car I actually baked some food I had bought for the weekend. Ive never forgotten the baked Granny Smiths apples that were a suprise find before setting off to drive home 250 miles one friday night. What a treat.
Try a black car in the Aussie sun! Should come with a health warning... Love tha apple story! 🙃
 
I'd say this is quite likely too.

With mine, if it doesn't immediately stop the car on coming to rest, sometimes just giving the gear lever a slight wiggle about the neutral position will cause the S/S to kick in and kill the engine.
The operation of S/S has been intermittent. I did get it to activate stop once by wiggling the gear stick in neutral. I hooked up the MES and can see it was ready to stop. Shame you cant actually see the neutral signal status in MES. It just doesnt always kick in. I dismantled the covers around it to get a close look at the neutral sensor. It all seemed secure and the link arm with the gear stick was moving. I carefully managed to remove it. The pin clips holding it are quite tricky to remove. I tried to do a bench test but it is not a potentiomter or proximity switch. The symbol in the e-learn diagram shows an op amp so I think it may be a Hall effect device so signal will be only a small value. Hence it needs the calibration routine. I fitted it back and redid the calibration. It initially said failed but worked on the 2nd attempt. The start stop did work on a test drive but we will see how it is in normal service. I think I will buy a spare used sensor through ebay. New one is £200 from Fiat Workshops
 
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The start stop has worked intermittently . I checked with my MES and can see it shows ready to stop on occasions but just doesn't .
I had bought a replacement neutral sensor from Club Italia and fitted it today . I also bought some 6mm star clip fasteners on amazon as they really are intended as single use only. Getting the old clips off is the worst part of the job. I did the neutral sensor learning again for the new one . On the test drive Stop-Start worked 5 times in a row once I had the engine warmed up . Fingers crossed , time will tell.
 
There's nothing artificial about the 500 hatch wiring fault.

That's real stupidity.
Thats very true! but at least that goes wrong in a predictable way that many of us can understand!!:unsure: unlike this stop/start problem where the OP must feel like they are chasing an electrical poltergeist around a maze! -blindfolded!.:rolleyes::cry:.
 
Thats very true! but at least that goes wrong in a predictable way that many of us can understand!!:unsure: unlike this stop/start problem where the OP must feel like they are chasing an electrical poltergeist around a maze! -blindfolded!.:rolleyes::cry:.
Frankly, if my S/S ever fails to work, and a new battery doesn't solve it, I'll just turn it off permanently and forget it. 🙃
 
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