Seems this is a common issue, not just on the Yeti, My three year old 1.2 tsi seems to have developed this problem, If left to stand for a few days there is considerable voltage drop. Not a big problem there is a power point handy and I have a low amperage "smart" charger. But annoying because I am sure there is something not working correctly. So fully charged the battery, disconnected the earth  and left it stand on the car, no voltage decay in over 36hrs using a digital meter. That eliminates the battery as being the problem. Next step check for parasitic voltage drain using faithful digital meter between battery negative and negative battery cable. Everything shut down but doors unlocked left to stand for 2 hours .... yes 2.0 amp current flow so pulled fuse f8, current flow drops to 0.5 amps (I know the handbook says there is a fuse in the cockpit fuse box on this yeti the location is vacant, I suspect because this head unit has no CD) I have now reset the head unit to factory defaults going to check again for voltage drop. Has anyone else out there had a problem with the bolero causing Battery drain ?             

What was the resting voltage reading? The fact that it didn't drop over 36 hours isn't proof of it not being a problem.

 

just changed my battery on the 1.2 TSi and it was only 30 months old, the OEM battery is pathetically under powered and mine was knackered, wouldn't take a full charge even after 60 hrs and rapidly went down to 12.2 volts, surprised it managed to start the car even though it sounded OK.

 

got a much more powerful one from Tayna delivered next day, 
S5 A08 Bosch AGM Car Battery 12V 70Ah Type 096 S5A08
https://www.tayna.co.uk/car-batteries/bosch/s5a08/

 

also got a memory saver  for £9.25 on ebay that worked great and kept all the settings when changing the battery over
https://www.ebay.co.uk/itm/381527997496?ViewItem=&item=381527997496

Edited 11 February, 20197 yr by Halford

1 hour ago, Llanigraham said:

What was the resting voltage reading? The fact that it didn't drop over 36 hours isn't proof of it not being a problem.

 

True, but a 2A current draw from the vehicle suggests there is something in the car that's not right.

True, but haven't we seen in the past that there is an initial high draw and that this then reduces?

On my Superb iii, standby current drain is around 12-13mA, every 20-30 minutes it will go up to approx 50-60mA for several seconds before coming down again. So an average of approx 15mA.

 

If you open a door or do something to the car,  the car electronics spring to life and draws a few amps, after closing it takes a good 2 or 3 minutes for the various subsystems to shut down one by one, you can hear some clicking as this happens.

 

 

Thanks for the responses but I know that these systems take a while  to shut down, the car had been standing over night untouched with the earth cable disconnected.checked the drain without opening doors or anything else. I am not looking at mA it is 2 amps, left it a while checked again same result. Even tried another meter same result. Looks like the Bolero is on the fritz.

 

Considerable voltage drop if standing for a few days!!!
With a 2 amp draw the battery would be knackered in 2 days.

1 minute ago, Urrell said:

Considerable voltage drop if standing for a few days!!!
With a 2 amp draw the battery would be knackered in 2 days.

 

A 2 amp draw would mean a flat battery in a little over 24 hours, assuming its reasonably charged to start with. The battery is also unlikely to survive a complete draindown. So I rhink its unlikely to really be 2 amps continuously.

 

Don't know how the OP is measuring the drain, a series meter is not a good way of doing it because it introduces voltage drops. Especially if the car is configured for micro hybrid smart charging with a current sensor built into the negative battery terminal connector.

 

Battery voltage varies with temperature.

 

 

 

Don't just pull fuses, it can prevent the car going 'to sleep' causing excess current draw.

 

Instead, bypass the door and bonnet switches, disable the interior monitoring sensors and then measure the mV over each fuse after a couple of hours.

 

You can find the guide in this thread: 

 

I was advised to turn the switch off Automatic if leaving the car unused for any length of time.

Tracing a battery drain in one of my caravans I was loaned a dedicated meter with fuse

shaped prongs (different sizes) around £100 to buy.

How is it that on my bog standard and un-modified, 8 year old 1.2 Yeti I've never had a scrap of trouble with the battery?

The car either sits in the garage or on the drive and starts first time every time.

Sometimes it doesn't move for three or four days.

 

I did change the battery for a like for like replacement (Varta Blue Dynamic D24 027 £67.50 delivered) last October but only as a precaution given the age of the thing. It hadn't failed but I simply thought with winter coming it would be a sensible thing to do.  I kept the old one and it holds its charge almost 100% ... I don't know why I kept it, it'll probably never get used for anything. In fact it probably didn't need changing at all.

 

So why am I not needing to pull fuses out or bypass this or turn off that or upgrade to a battery that cost twice as much as mine?

 

 

 

 

 

 

Edited 12 February, 20197 yr by oldstan

4 minutes ago, oldstan said:

How is it that on my bog standard and un-modified, 8 year old 1.2 Yeti I've never had a scrap of trouble with the battery?

The car either sits in the garage or on the drive and starts first time every time.

Sometimes it doesn't move for three or four days.

 

I did change the battery for a like for like replacement (Varta Blue Dynamic D24 027 £67.50 delivered) last October but only as a precaution given the age of the thing. It hadn't failed but I simply thought with winter coming it would be a sensible thing to do.  I kept the old one and it holds its charge almost 100% ... I don't know why I kept it, it'll probably never get used for anything. In fact it probably didn't need changing at all.

 

So why am I not needing to bypass this or turn off that or upgrade to a battery that cost twice as much as mine?

 

?

You are asking why You have not had trouble... Surely you don't want, nor expect trouble?  I can leave my car for weeks and return to it, it starts and runs as it did when i last used it... This, I conclude, is normal. Leave it for six months, I expect a flat battery!

You changed the battery as a precaution... Admirable as most will wait for it to go flat at least a few times, prior to doing this but to ask why YOU have no issue is like a skinny person asking a fat person why they too, are not fat!

 

4 minutes ago, oldstan said:

 

 

 

 

 

2 minutes ago, mrgf said:

 

 

 

I don't think you cottoned on to the fact that I was speaking somewhat "tongue in cheek".

 

I was, as others here who know me better, noting that the assembled brethren are talking about about an assortment of malfunctions and odd characteristics and subsequent rectifications that warranted an exchange of views  (which, of course, is what a forum such as this is great for) .... whereas I was merely expressing gratitude for my good fortune (and feeling a bit left out of the conversation )

Interesting that the older cars do not seem to have this issue, Reading these responses it does seem that yanking fuses is not the best way to go, VAG  recommend checking the voltage drop across each fuse until the problem one is found.  Clearly this a generic problem on the current generation of cars,  to the extent that VAG have released a procedure to diagnose the cause. I have now fully charged the battery (smart charger to 12.84v) and  will see what happens over the next 24 hrs.

Has the OP actually said he has any problems regarding starting etc? He certainly is obsessed with "voltage drop". I'm not sure he has an in depth appreciation of micro hybrid charging/energy recovery

schemes used in these cars, AGM, EFB technology, surface charge, resting voltages, temperature effects, state of charge (target and actual) and health of charge.

 

Just because his battery has dropped to 12.2v after a few days stood is not automatically indicative of any fault, especially if you open the car to pop the bonnet, when the car electronics spring to life and battery voltage is depressed considerably and will take 30 minutes or more to recover after all subsystems turn off. 

 

He should realise his battery is rarely fully charged under modern micro hybrid schemes, typically it will be held at 70-80% SOC, but often it can be somewhat lower depending on previous driving cycle and power consumers being used.

 

I don't for a minute believe he has a constant 2 amp drain as the car would not start after 24hrs stood never mind a few days.

 

 

5 hours ago, oldstan said:

How is it that on my bog standard and un-modified, 8 year old 1.2 Yeti I've never had a scrap of trouble with the battery?

The car either sits in the garage or on the drive and starts first time every time.

Sometimes it doesn't move for three or four days.

 

I did change the battery for a like for like replacement (Varta Blue Dynamic D24 027 £67.50 delivered) last October

 

you obviously don't have start-stop on your old yeti, which is why the newer versions of the 1.2 need special batteries,

afraid that as usual progress means more expense

 

Ah ... an answer that I can understand and which puts things into perspective.

No, there's no stop and start - and I think I'm grateful for that.

 

Do Hybrids like the Kia Niro or Toyota Yaris and Prius have stop start?

OK here is the latest....Battery at full charge 100% after slow charge using computerized slow smart charger  12.84v

20 hrs later..parked nothing touched doors not opened, not run now 12.14v  i.e. about 50% charge

I will leave it sit for about another 12 hrs touch nothing and check again.

I simply cannot accept that this is "normal" fact is in 3 days voltage will drop to the point where everything shuts down.

Remember if the battery is disconnected from the car it holds 12.57v for over 36 hrs, I have not run a load check on this battery I probably should do that.

Malfunctioning Bolero's are not exactly unheard of, some have been replaced under warranty.    

2 hours ago, xman said:

Has the OP actually said he has any problems regarding starting etc? He certainly is obsessed with "voltage drop". I'm not sure he has an in depth appreciation of micro hybrid charging/energy recovery

schemes used in these cars, AGM, EFB technology, surface charge, resting voltages, temperature effects, state of charge (target and actual) and health of charge.

 

Just because his battery has dropped to 12.2v after a few days stood is not automatically indicative of any fault, especially if you open the car to pop the bonnet, when the car electronics spring to life and battery voltage is depressed considerably and will take 30 minutes or more to recover after all subsystems turn off. 

 

He should realise his battery is rarely fully charged under modern micro hybrid schemes, typically it will be held at 70-80% SOC, but often it can be somewhat lower depending on previous driving cycle and power consumers being used.

 

I don't for a minute believe he has a constant 2 amp drain as the car would not start after 24hrs stood never mind a few days.

 

 

Yes indeed the car if left for 3-4 days the battery will in the discharged condition to extent where all electrics have shut down, that is most certainly not normal, if the Bolero is disconnected the battery drain immediately drops to millivolts. In checking the drain the car again is left to stand untouched for a minimum of 2 hrs prior to checking.

1 hour ago, piewacet23 said:

OK here is the latest....Battery at full charge 100% after slow charge using computerized slow smart charger  12.84v

20 hrs later..parked nothing touched doors not opened, not run now 12.14v  i.e. about 50% charge

I will leave it sit for about another 12 hrs touch nothing and check again.

I simply cannot accept that this is "normal" fact is in 3 days voltage will drop to the point where everything shuts down.

Remember if the battery is disconnected from the car it holds 12.57v for over 36 hrs, I have not run a load check on this battery I probably should do that.

Malfunctioning Bolero's are not exactly unheard of, some have been replaced under warranty.    

 

Looking at your report suggests to me that your battery is knackered. It also suggests that you don't understand how batteries work. I know from experience that a caravan battery, sat in the shed and not connected to anything, will gradually reduce voltage, and the greater and quicker that drop if the battery is failing. My own previous Yeti had all sorts of strange "problems" until I did a battery test and found the resting voltage was only 11.8v.

People don't realise that as soon as a battery reduces to a 50% charge it has been damaged. The lower the percentage charge the greater the sulphation. The more sulphation the worse the battery gets. They are plenty of stories about this on another site I frequent, but there they are often talking about 12v battery banks of 3 or 4 batteries that end up costing them £200 or £300 to replace because they have let their voltages drop to damaging levels.

3 hours ago, piewacet23 said:

if the Bolero is disconnected the battery drain immediately drops to millivolts.

I take it you mean milliamps, if so you have found your problem.

99% of times the parasitic current draw is about mounting new electronic devices (radios, amplifiers, alarms, central locking, chargers, etc.)

99% of times the garages wire them fast by ear using new power circuits with a fuse-on-wire and 'mandatory' cheap insulation tape. The quality of their work is pi$$-poor at best.

Note: maximum stand-by current should be less than 25 mA.

2 hours ago, Llanigraham said:

 

Looking at your report suggests to me that your battery is knackered. It also suggests that you don't understand how batteries work. I know from experience that a caravan battery, sat in the shed and not connected to anything, will gradually reduce voltage, and the greater and quicker that drop if the battery is failing. My own previous Yeti had all sorts of strange "problems" until I did a battery test and found the resting voltage was only 11.8v.

People don't realise that as soon as a battery reduces to a 50% charge it has been damaged. The lower the percentage charge the greater the sulphation. The more sulphation the worse the battery gets. They are plenty of stories about this on another site I frequent, but there they are often talking about 12v battery banks of 3 or 4 batteries that end up costing them £200 or £300 to replace because they have let their voltages drop to damaging levels.

OK so I know nothing about batteries you believe this one is Knackered, then please explain to me why there is a very large drain on the battery with everything shut down, this drain is dramatically reduced the instant the Bolero unit is isolated from the cars electrical system ?  Is that a symptom of the battery failing ?  

43 minutes ago, Urrell said:

I take it you mean milliamps, if so you have found your problem.

You are correct I do mean milliamps, everyone here is telling me I know nothing, its normal, or the battery is knackered. Simple situation with everything shutdown there is a big draw on the battery. Isolate the bolero draw is considerably reduced. Not exactly brain surgery is it ? I am not playing with this, after a couple of days with the car parked the battery has degraded to the point where it will not start the car. It seems asking about problems of this type, issues  with these head units are not unknown. 

Edited 12 February, 20197 yr by piewacet23