[charlie8]

Hello

Few years ago had the infamous ( I see still bouncing around here ) ESC light at 50 mph and glad the outcome is still helping people 

Now I have another mystery, although not so serious in affect and maybe much easier to understand

I have a A symbol in yellow on the dash from start ( well about 5 secs after start, it flashes , then stays on ) and wont go away. So that is the stop/start symbol which I think comes up when 'stop' in enabled. The yellow light on the switch always on.

So back story. Left for 2.5 weeks when on hols, a slightly longer crank to start, but drove for a bit, before resting up again for ~4 days.  Starting then and this issue starts. After driving a few miles ( 30 mins ) , I noticed it went away/out on the next +1 start. Then the next day on again and stayed on. I charged battery on AGM charger, which got to full charge after ~6 hrs, put back in. Still now the symbol stays on. The battery is over 7 yrs old ( 98K ), so thought this was low on charge delivery not voltage and bought a new one, which I prob do need anyway as stop/start was at best only working after a good 30 mile journey and thats  while for a battery. ANyway no cigar with new battery

Tried - leaving with no key in lock for 4 hrs ( many say to allow ECU to learn new battery condition ), driven about 10 miles, done 2 quick start/stops ( some say that resets the previous battery condition stores ) anyway still same issue

Car seems to drive OK, mpg good. New OBD codes stored. Does sounds gruffer ( like a small hole in exhaust when just start, but prob my imagination as I'm looking too hard )

Basically its like the car thinks its permanently in stop mode ( or is that a green A symbol ) so something is confusing it. What I have gone back to is the fact its started after leaving the car for a while and like its telling me it can not give auto start/stop at the beginning of the journey, and the flash before going perm on is the test failing.  But why with new battery is the same prevailing - do I need to clear something. WHen I phone Hyundai about battery they said any 70ah, 760 A AGM will do, no pairing to do, so went for non OEM. Even when charging the old one though it stayed on

Any clues - cannot find anything in search or wider internet

[Dazzler]

  

Thanks for the detailed explanation.  You have certainly done everything I would have suggested except perhaps disconnected the negative terminal of the battery for a minimum of 30 minutes to reset the ecu. Although when swapping batteries you may have actually reset the ecu if you took your time.

My only other suggestion would be to find a list on here or in the manual of all the things that can stop the stop/start working and work out if any of those may be confusing the light...

[charlie8]

Just found something from Kia ( same layout ) - although quite a long process - I must have done this inadvertently as its had 4 journeys, 1 night, 1/2 day parks and 2 extra B2B starts. So I reckon its been calibrated, but just cannot say for sure and no way to check, still 'feels' like I have some past condition stored.


"Ensure the AGM battery is placed correctly on the battery tray. In all cases, an AGM battery must be installed and the battery sensor calibrated for the ISG system to function. After the battery has been changed or disconnected, the battery sensor must be calibrated. After connecting the battery, start the engine at least once. Then park the car for at least 4 hours with the ignition off. After the 4 hours, the engine should be started two times. At this time the battery sensor will be calibrated."

[charlie8]

THanks Dazzler, my hot swap would have been about 6 mins, so no where near  the 30 mins to reset the ECU, but would have thought the re-calibration would have forced the new anyway by now. Maybe a few more days of driving and leaving will help and will just go, although in the UK its sun city right now so in the rag top and not wanting to commute in the tractor, reliable as it is ( or was  )

[Dazzler]

Us Aussies even the more technical ones aren't real cluey on the stop/start system as I don't think any model of the i30 to date has been delivered in Australia with that feature. 

Yes, anything Kia should be equally relevant. 

[mickd]

Us Aussies even the more technical ones aren't real cluey on the stop/start system as I don't think any model of the i30 to date has been delivered in Australia with that feature. 

Yes, anything Kia should be equally relevant. 

C'mon dazz !!, our stop /stop is key operated 

[Dazzler]

 

[charlie8]

I did the ECU reset, just to be sure, 1/2 hr battery disconnect and then 4 hr wait. No difference

Manual states that a flashing yellow 'A' on start up with persistence, shows that a sensor has issues and so auto start/stop is disabled.

I have been through all other functions on the car and everything works, cruise control, speed set etc - at any speed no warnings, MPG is well up, so car is functioning well - meaning driving sensors are good

I thought the start/stop switch may be at fault ie its permanently off, but if I quickly switch on start up the dash writes out manually de-activated, so it registers the switch change - thats OK
Seat belt sensors work and light up when I remove - so thats another check ( auto stop wont work unless driver is in place )
All clutch switches must be good as no other driver warning
Coolant level is good - presume if sensor wrong, would get a low level light also

Only thing I can think of is the battery temp sensor - does anyone know where that is/how to test ?
Another one is the brake vacuum low - how to test that ?

Just cannot be dong with paying so much to ask Hyundai to plug in their s/w, so before I do looking if any clues from anyone ?

[charlie8]

Hmmm, pulled the plug on the -ve sensor, made no difference - so either thats it or just puts and err behind an error

Anyone know how to test the battery sensor - I think it measures charge load and temperature ?