[BunnyKillBot]

Hi guys,

I have a problem with my ISG not working. I am aware of the long list of inhibitory conditions etc. When i got the vehicle last year it was three months old. The ISG didn't work at all so I put it into the hyundai garage who diagnosed the battery as faulty, replaced and charged. The ISG then worked properly for a bit. Then less. Then less. Then less. Now, it happens once in a blue moon if at all to the extent I actually applaud it when it does work. I just put the vehicle in for its 20k service and got them to take a look at it. I can assure you the vehicle is not being used inappropriately for battery charging conditions, mostly motorway miles and regularly. It is also the active, so no heated seats or fun toys that might be excessively draining the battery.

 Initially, they did the usual fobbing off that there are allot of inhibitory conditions etc, but the outcome is pretty much the same as before. This time, the battery is 'healthy' but showing as poorly charged. For some reason, the battery is never properly charging from the alternator, enough to start, but not enough for the ISG to actually work.

So far I have been told
'Lots of people like that it doesn't work because they find it annoying' - Given its a marketed feature of the vehicle that exists to reduce fuel emissions, surprisingly I would rather like it to work please. Given that this emissions saving feature, quite literally puts the vehicle in a £0 tax band but barely, if ever works, surely that is a con/fraud?
'You will have to occasionally trickle charge the battery yourself to top it up' - Err what? No where in the marketing does it state ISG subject to amateur home battery charging. The vehicle should be able to keep itself topped up under normal conditions.
'The smart alternator only charges the battery when its under load, i.e. with the lights on and wind screen wipers on' - This counter intuitive statement, even if true, believe it or not i do drive at night with the lights on, and use the wipers when it rains......

From when it actually worked, i did tend to notice:

Fan blower on 3 prevented it from working, not the stated 'maximum' of 4
It may have worked more consistently if the AC was off. The AC is usually on.


So, forum denizens, what say you. How do i tackle the barely-couldnt-care-less-nothing-we-can-do dealership garage? Am I alone in my ISG suffering. Is it tax fraud if an emissions saving feature doesn't reliably work, and those users should actually be paying tax?

[asathorny]

One of our members is very knowledgeable on this, and many other subjects, and has done quite a lot of research thereto related.  So, over to you Alan 

[Johnno]

just done a google search and find your not the only one with this problem. Seems a bit of a flakey system and other manufactures seem to suffer the same problem if the parameters are not met.

[Phil №❶]

The alternators fitted, are more than capable of keeping the battery at the required level for ISG functionality. So IMO, the voltage regulator is faulty in the alternator. this can only be determined at the dealership by testing and thorough inspection of all components. You need to get your message across to the service department, that any response from them other than "it's all working fine", is an unacceptable response.

It's under warranty, so it must be made operational.

Failing that, find a better dealership.

[Dazzler]

  Bunnykillbot and 

The wording of you post was excellent and I fully relate to your frustration. I don't currently have ISG but would feel exactly the same in your situation.

I would be contacting your local Hyundai head office and demanding they ensure your vehicle is modified to a condition where it performs as advertised (and expected) 

[Johnno]

Try it with the AC off and everything off that you don't really need to be on. Had a look on the Kia forum and this as been ongoing for years. Even one guy as only had the car for one week and it stopped working. I read somewhere that there is 39 parameters that the ECU checks to allow it to work and if one of these parameters don't meet the requirement it will disable the ISG.

It also states the if the battery drops to 76% that will also disable it. I dont have ISG but one thing I've noticed on my car, if I park up and switch everything off and just leave the radio on for about 10 minutes a warning comings up on the sat nav display
warning battery low start engine.

I'm wondering if the ECU software is reading the battery voltage incorrectly. ie a flaw in the program coding? it could be right across the range of models


 

[BunnyKillBot]

Try it with the AC off and everything off that you don't really need to be on

I will not do this, because AC, wiper blades when it rains and lights when its dark, even the stereo, are basic features if not rights in 2013. Turn of those power hungry electric heated seats i could understand, but AC? No way. Its a dehumidifier, nothing special. If the ISG only works with lights off, wipers off, ac off, radio off etc, it is clearly unfit for purpose and not as described.

A car alternator is a powerful mobile electrical generator. In this day and age, it should be impossible for the battery to ever run low. The ECU can easily determine if the battery needs more charge, inject a little more fuel and or set the alternate output, at the cost of mechanical power.

[Johnno]

What I'm trying to put across is that the ECU is saying the battery is low when its not like on my chariot that doesn't have ISG

All models with ISG be it Kia or Hy are having the same problems as you, more so in winter than in summer.

The only reason i say turn things off is to determine what is causing the problem or your get nowhere to solving the problem. 

 
Faulty Isg On Ix20 - Hyundai Forums : Hyundai Forum

Kia ISG (Idle Stop & Go) System; How It Works? | Kia News Blog

ISG not working - Kia Owners Club Forums

I agree with your way of thinking,[ Is it a tax fraud]     maybe its Hy way of getting around for the car to be classed as zero road tax?

[BunnyKillBot]

Hi,

Having got the car back from its 20k service and an overnight trickle charge, with the stars aligned and perfect conditions i decided to do some testing for research purposes. Testing is actually quite easy, because if you successfully bring the vehicle to an ISG stop, then turn things on and off, anything that is an inhibitory condition will cause an engine restart. I have identified the following, non-specified inhibitory conditions and can video evidence if required.

1) The fan blower on 3 or above is an inhibatory condition for ISG purposes, not the stated 'maximum' of 4.
test - With the fan on 2 or below, bring the vehicle to a successful ISG stop. Raising the fan to 3 or above triggers an engine restart
2) The front windscreen demister selector is an inhibatory condition for ISG purposes.
test - With the fan on 1 or 2, bring the vehicle to a successful ISG stop. Pressing the front windscreen demister button triggers an engine restart.
further test - With the fan on zero and the windscreen demister already active, bring the vehicle to a successful ISG stop. Raising the fan to 1 or above triggers an engine restart.

Having got the thing to actually work, in the last 5 minutes of the 30 minutes test drive, the ISG went from a condition of working, to not working at all for my last three stops. No known inhibitory condition was present. The vehicle then sat parked for 20 minutes. The ISG worked again on the next drive.

So there are really two competing problems here that are frustrating and causing this issue.

1)When it doesn't work, it doesn't work - There appears to be a fault with the charging system that is, over time, allowing the battery to drop below the 83% required for ISG function under normal use. The hyundai garages are not forthcoming with an resolution other than an advisory to trickle charge the battery, at your own discretion, to bring the charge back up to the required level.
2)When it does work, it doesn't work - There is a long lengthy line of inhibitory conditions, some known and some unknown, and zero user feedback as to what is causing the inhibition beyond 'ISG disabled'.

[Johnno]

I think I would be p*&^$d off if that's the best the garage could come up with by trickle charging every time  you want to use it.

Seems that the ISG system needs a bigger amperage battery to maintain the required level of charge for the system to operate or a larger alternator. There seem's a very fine line between charge and discharge condition for the system to work.

Hy and Kia must know of this problem as there is a lot of owners complaining about it and have done nothing to resolving it and only state what you must or must not do for it to work which I find is poor. You would expect the system to work  with all the electric's switched on and  not once every now and again.

I know the car is still under warranty and your local Hy garage aren't much help, but how about going to a auto electrician and asking for some advice on how it could be resolved.

[eye30]

Glad i don't have Isg

Sent from my ONE TOUCH 983 using Tapatalk 2

[asathorny]

Glad i don't have Isg

Sent from my ONE TOUCH 983 using Tapatalk 2

 

[The Gonz]

What a gluteus maximus equus! I can see backyard hacks to disable ISG in the future.

[AlanHo]

I carried out numerous tests on my last i30 and my current Kia to reveal the mysteries of ISG - without a firm conclusion.

I am more than aware of the host of conditions that must be satisfied for ISG to work and need not detail them here.

My present car is the most frustrating - even though the engine usually stops when it should. The problem is that it stops OKvbut sometimes does not start again when I depress the clutch - leaving me scrambling to start the engine with the key before millisecond muggins in the car behind starts tooting - the impatient bastard possibly under the impression I have nodded off.

KIA have tested the car - but needless to say the problem would not reveal itself in their hands. They offered to have the car in overnight to recharge the battery - stating that there is a special procedure to do this.

The battery must be disconnected - both terminals - then connected to the special ISG charger overnight. After the charge is completed the battery is reconnected and the car left for 4 hours for the battery control module to re-learn itself before the engine is started.  The battery control module is a black anonymous lump to the side of the battery on the positive lead.

They told me that If you fail to charge the battery properly - or use a jump starter - the control module will be damaged.  Oooops  - I didn't know that - and there is no warning on the battery or in my owners manual to that effect.
 
I have been told by a neighbour (who is a VW technician) that with their cars the alternator normally only charges a battery with less than 75% charge when you are slowing down and have your foot off the accelerator. This is to aid fuel economy by harvesting maximum energy when you are braking or on the over-run.

To test out this theory on my KIA, I bought a small digital volt meter which plugs into the cigar lighter. I have proved that when belting down the motorway the voltage remains in the range 12.2 to 12.8V but will suddenly increase to 14.2V when I lift my foot off the loud pedal. It will fall back to about 12.8V when I acelerate again. I hasten to add that I have not had my cheapie volt meter calibrated and these readings are relative.

I have now given up experimenting - life is too short - but my car is due its second service next month and I will report the ongoing problem to them yet again.

[The Gonz]

 

[asathorny]

 

[Phil №❶]

I feel sorry for all those buyers, duped into thinking they were going to save money with ISG. Purchasers, if a salesman tries to tell you this is a feature, Clearly, this is a tax evasion exercise and at increased cost to the consumer, in purchase, maintenance and fuel consumption costs.

Basically, it doesn't work. 

[Dazzler]

I feel sorry for all those buyers, duped into thinking they were going to save money with ISG. Purchasers, if a salesman tries to tell you this is a feature, Clearly, this is a tax evasion exercise and at increased cost to the consumer, in purchase, maintenance and fuel consumption costs.

Basically, it doesn't work. 

I believe Mazdas version works ok...

[Shambles]

It is a rather annoying feature, to me. I see it as costing me money in fuel.

First thing I do (if I remember to do it) is hit the "ISG Off" button just before I crank the engine. It really does get on my wick if I forget to do this, trundling a few hundred yards down the road only for my cold engine to cut out as I pull up at the first junction.


ISG 

[Phil №❶]

I'd take that switch and determine what "off" actually means.

e.g.

Off could be Earth,

or could be connect,

or could be either of the above with a resistance.

Once determined, wire it up permanently.

[The Gonz]

... wire it up permanently.

There's the fix!

[Johnno]

Them figures are  about right on the charging Alan.

I'm glad I didn't go for one of them it would do my head in

[Johnno]

Looks like it needs a constant voltage supply at all times, it can't be that hard for the boffin's [just checking spelling make sure i didn't put buffoon ] at Hy to come with a solution, like a in line voltage regulator solely for the ISG 

[asathorny]

I propose we install a magneto like we have in prop aircraft which means the engine isn't reliant on the battery we could incorporate the ISG into the magneto circuit....

So... now I have solved the problem I want Gonz and whomsoever he nominates to assist in designing and marketing it and them him and I to split the profits 50/50.

We will soon be millionaires 

 

[MarkC]

Don't have ISG on my bus thank goodness. I did have it on my previous car, a VW bluemotion Golf. Happy to say that the system never caused any problems for me. Mainly because I always switched it off 

[Phil №❶]

 

[bigwhitetruck1]

My i30 has the same issue as stated in this post
Intelly stop & go my Ar$e

Does not work 80% of my journeys till I trickle the battery for a while

[Wingerdave]

Just one question....  is ISG ?

[Asterix]

Just one question....  is ISG ?

Start/stop system

In Hyundai terms:  ISG (Intelligent Stop & Go)

Read more here:  Hyundai |Blue Drive

[Wingerdave]

Aha, yes, i've got that. Probably the most useless option on the car IMHO. I take it you can't permanently turn it off ? Only a temporary disable with the switch ?