[i30ladyowner]

hi,
I have a 2010 Diesel i30 - ~37K miles. Recently serviced. Driving a good 300 miles weekly and no issues really. happy out !
My problem is now twice my battery has drained when engine is off  ( 20 -30 mins) and in just "power "mode ( sorry don't know the correct term) .
recent  scenario -  pulled in as needed to tak ephone  call , switched off motor just ( lights still on ) - 15/20 mins later went to start car and it failed to start ; signs being battery low.
Rang AA for jump start - confirmed its battery ; they checked the battery and nothing coming back faulting. Jump started it and it grand again.
I know - solution turn off the car the fully etc but really the car shouldn't fail like this is "standby" mode for only 30 mins.  there is something draining the battery badly when in standby mode.
Any insights on this one ?  Is this a common issue with this model ?
My 5 year warranty will be up in Nov so want to get this sorted before then in case its something more serious.

[Dazzler]

  i30lady 

Because you live in a coldish climate and your car is nearly 5 years old the battery would be approaching the end of its lifespan. Battery warranty is only 3 years maximum from memory (warranted by battery maker, not Hyundai)

I would just buy a new battery but you need to get the correct heavy duty version to suit your car.

[Asterix]

Hi i30ladyowner

 

A battery could get bad after 5 years, but many last longer. You say you leave the lights on for 30 mins, is that headlights (low beam) or just parking lights..?
I would never leave the car with the headlights on for 30 mins without the engine running. Your 300 miles weekly driving should be sufficient to keep the battery in good shape...

I would advice to get the dealer to test the battery, they can perform a more thorough test than the AA, I believe. If you have a battery charger at home, one of the new intelligent ones, then charge the battery to make sure it's fully charged.

[wbm00]

I charged mine up on the day it was picked up, it took a smart charger about 45 minutes to charge the battery to 'full' and so I'll be repeating this in a few days time to see whether the battery's charge is being maintained. It's my understanding if a battery is maintained in a 'full' condition it is less liable to sulphate.

It can help to alter your patterns especially in colder conditions to make life easier for your battery. For example, I've disabled the follow me home headlights and generally try to put the electric windows up while the engine is running. Some people switch headlights on before starting the engine - I switch them on only after the engine has started.

[Phil №❶]

Headlights only operate when the motor is running. The battery should be able to handle 30 mins of standby. I would check the charging ability of the alternator, if a diode is on the way out, it can cause a slow discharge while driving. Happened to me in a car with just a Alt warning light, could only be seen when driving at night, so of course, I got stranded. 

It's a fairly simple check with a meter 

[sundiz]

At least in my car the lights work when ignition is on and motor is not running. The lights usually work differently depending where the car is located. Different countries have different laws and regulations.

Cars are not desingned to work like that (30 min with power on). Thats why taxis, police and other "special" cars usually have a second (free time/ AGM) battery for situations like that. Generally starting batteries are only good for starting the car, not for long time current draining. That's why they recommend to use AGM battery if you have webasto, because normal batteries are not designed to give power for such a long times. If the car was in "power on mode" and the lights were burning no wonder it drained the battery. Just the H7 bulbs take 55W, making the total of 110W + rear lights (possible brake lights, possibly the glow plugs?), radio etc... there's quite easily 20 amp drain with all the lights and electronics.

I would not blame the battery. I think the problem has been between the seat and steering wheel  .

[beerman]

I was told once you drain the battery in diesels they are basically stuffed.  Because of the extra power required to kick over the engine, they never truly recover.

I replaced the battery in my 2010 ages ago, I also have done the battery in my 2011, and I live in sunny Queensland where were complaining about last nights 7 degree minimum. So I would say the battery is cactus.

That said I wouldn't leave the car in the manner you describe for any period of time.

[Phil №❶]

It really hinges on whether the headlamps were on or not, without the engine running. Without, it should have been fine, but with, that's another story. The starter on the Diesel is a reduction starter, according to my ear, so the battery drain should be quite minimal.

Still running our 2010 with the original batt. Touch wood !

[Asterix]

My 2008 / 237.000 km still runs the original battery   

[eye30]

Don't the headlights go off after a few minutes?

[Paolo5]

I had my diesel's battery replaced  by Hyundai (reluctantly) a week shy of its first year. The workshop manager told me that I was "lucky" that it wasn't a week later as the warranty for the battery would have expired.

The good news is that the replacement battery hasn't missed a beat since then...over 4 years ago....except for the time that I pulled into the garage and turned the engine off but neglected to remove the key. The lights were not left turned on. Like the episode of "Breaking Bad" when Jessie put the key in the RV's ignition so that it wouldn't get lost, my battery went completely flat over a period of a few days just by having the key in the ignition, not even turned to the accessory position. Lesson learnt.

[i30ladyowner]

thanks all for replies on this one , its  hard one to narrow down by sounds of it ; I know bit of user error here but I would have thought get more than 20 mins of a battery - note the headlights were - I might head to garage again for them to take a look and see if battery needs replacing ... but something niggling that something is draining battery badly .

[Phil №❶]

Have you had any other episodes of low battery since 

[i30ladyowner]

Nope all working perfect thankfully - but I make sure I turn everything off when I pull in to take a call

[ibrokeit]

If it is the original battery - I would look at replacing it... they don't last forever.   And as they age their capacity to store energy decreases.

Having said that, don't discount something like slow alternator charging also being a factor - things like that can happen and then it won't matter how good the battery is, because it can only store (and supply) the energy it receives - so it is probably worth while asking for it to be checked.

My OEM battery lasted 4 years, was reading 7.6V when it had to be replaced by a mobile battery service, they were surprised it had lasted.  Having said that in summer it can get quite close to 40^oC, so you can imagine how hot somethings get when standing in the sun.   Of course the cold can also have an effect.   New battery has a 36 month warranty.