Low Battery

Hi all

When I popped into the shop yesterday the kids wanted to stay in the car so I turned the tv on for them with the ignition off and a warning message came up on the screen saying that it would turn off in 3 minutes due to a low battery.

Any else experienced this?

Yes. Have a look using the search. Think essentially its an over-egged warning and nothing more.

Both my Audi & BMW's to this too, I concur with gw - the warnings are a little overzealous.

(01-04-2012 12:53pm)gw76 Wrote:  Yes. Have a look using the search. Think essentially its an over-egged warning and nothing more.

No it's not as mine said this twice and then the car wouldn't start.

The 10 minute warning seems a standard feature to stop the entertainment system draining the battery, yes probably over zelous.

If it's the 3 minute warning most likely a faulty alternator. That's what mine was and another Evoque the dealer fixed the day before mine with exactly the same symptoms.

Check the thread Yet another problem LOW BATTERY WARNING.

Tony

Mine does it but it's intermittent!! Care is going in to the dealer so we'll see what they think

Mine is booked in on Monday.

Hi there. Exactly he same happened to me. It was the alternator charging insufficiently.

My understanding about this is related to the battery performance of cars with stop start and regenerative energy systems.

The batteries are special and have to have spare capacity to absorb the energy on overrun and hence the battery performance level is designed to be lower than a normal battery, hence manufacturers are putting these shut down timers on to prevent the performance from falling that bit too much. As you all know today's technology is all about compromises.

I have a friend who works for banner batteries and he explained this to me recently, can't remember the name for the new batteries but will dig it out, he has a new Volvo V60 and that has a small 12v battery next to the normal 12 v battery, like a motorbike battery to allow the basics to work when the stop start kicks in.

I will find out the technology and share it with the forum

Dual batteries are hardly new. My 10 year old SL55 AMG has a battery in the boot to power all the non-essentials and a separate battery in the front with zero external static drain to start the car if the other is flat because it's been standing at an airport for weeks.

The issue is that lead acid batteries are designed to provide the very high currents required to crank the engine - itself made more difficult with diesel engines and in the cold - and not to power anciliaries for a long time without compromising their ability to start the car.

So, there's a time limit for the stereo. Better that than getting a reputation for flat batteries and AA/RAC call-outs.