Hey all, new to this forum, enjoying my 500 apart from a annoying gremlin which just popped up.

Got an issue with my 500, the start stop does not work, I was driving it earlier and the start stop is unavailable message comes up with the start stop symbol on far right, in addition to this, the warning triangle on the bottom left came on too. I pressed the start stop button and as expected it did not do anything. When i got home i disconnected the battery via the quick release and connected it immediately. I started the car and the lights went off, i took it for a drive and the lights never came on but the "start stop unavailable" kept showing when i was coming close to a complete stop, it'd go away when i was moving, pressing the start stop button to switch it off the message "start stop disconnected" appeared and when pressing it again to activate it would say "start stop activated".



The way start stop works is when you come to a complete stop at a set of lights etc, take the car out of gear, foot off the clutch and the start stop engages, then if you want to get going again, you simply press the clutch and the engine fires back into life again - mine does not do it i'm afraid, however it does something else which is baffling me. Put the car in any gear and let go off the clutch when standstill so it stalls, but my car does not stall, it's in start/stop mode, i can freely move the steering wheel, all electrics work, not something a stalled car would do, also, when i press the clutch, the car fires back into life.

At first i thought it was a battery related issue, but since discovering this, i thing it's something else, the start stop system is working but in the wrong manner, has anyone else experience this and maybe could shed some light onto this?

Thanks all.

The system continually monitors the state of the battery and any electrical demand, and assesses its ability to restart the engine. If the system decides it may not be able to restart the engine instantly, it will not stop it, and give you the message you've seen.

Forcing a stall, will override this. The engine has stopped, so when you press the clutch it will try to restart the engine, and apparently is succeeding, but this may be using more battery power than it would otherwise wish to use, or it may take a moment or two longer to actually start.

Usual cause of your symptoms is a battery that is weakening. Some time in the near future you may well need a new battery. Then, if the car could sneer, it would say, 'told you so'.

If you wish, find someone who will do a battery test, Halfords offer these free I think. They stick a heavy load across the battery and the tester gives the results.

Hello and welcome to the forum.

S/S on the 500 is not particularly reliable and will stop working if the battery is not in tip top condition, or if any of the sensors have failed or fallen out of tolerance. The battery is by far the most likely cause; even batteries which test as good can still be sufficiently degraded to give S/S problems and the only sure way to rule out the battery is to replace it with one known to be in excellent condition. S/S will stop working a long time before you notice any difference when starting the car.

So, unless you are certain the battery fitted to yours is under two years old, don't bother wasting your time testing it, just go buy a new replacement - it'll need one soon anyway, as they rarely give acceptable S/S performance beyond three years. You must buy a replacement that's rated for S/S use; it'll cost you around £100 or so if you shop around; a franchised dealer will likely charge you at least £250. Non-S/S batteries will not work properly for more than a few months, so check the one fitted now to make sure it's rated for the job - some used car dealers have been known to fit cheaper non S/S batteries to get the cars off the forecourt.

Fortunately S/S is a 'nice to have', not a 'must have'. On a 2011 car, unless you are going to tinker with it yourself, if fitting a new battery doesn't fix the problem, I'd just turn S/S off (on older cars, you may need to do this each time you start; it can be permanently disabled on newer ones). Fixing it will likely cost you more than the fuel you'd save over the remaining life of the car.

IMO for all but the most urban drivers, the extra cost of more frequent and more expensive battery replacements will more than wipe out any small savings in economy you may get from the S/S system.

Thank you so much for your replies, excellent, i'll replace the battery and take it from there. In all honesty, this is the first time the car is being driven after 5-6 weeks too so it does make sense.



Again, thank you.

aa89 said:

In all honesty, this is the first time the car is being driven after 5-6 weeks too so it does make sense.

Click to expand...

After 5-6 weeks standing, even a first class fully charged battery will likely have self discharged sufficiently to prevent proper S/S operation.

If it's been standing that long, it's worth recharging the battery before splashing out on a new one. The system should self reset after a charge or a battery change, but it may take a few cycles to do so.

If you do change the battery, the good news is that the radio code is stored in the body computer, so the only thing you'll need to reset is the clock.

I think you have found the problem. My 2011 500 had a new battery early this year. On Monday we returned from a holiday and the car started instantly having been parked while we were away, but the start/stop was not working on the journey home. However, it has been fine ever since. I suspect that the lack of use was sufficient for the battery to have lost enough charge for the S/S to stop working, but has since received sufficient charge to restore its function.

Thanks once again, i just had a new Exide battery fitted and it has resolved the start/stop issue.


Thanks all once again for your help