Brand new battery drained

[RubySlippers33]

I have a 2 month old 12 plate Toyota Yaris T-Spirit with smart entry/start. I went on holiday for 2 weeks, leaving it in my garage and when I returned at the weekend, the car wouldn't start at all. It wasn't especially cold or anything like that while we were away. I 'phoned the dealership and described the "symptoms" and was told that it sounded like the battery had drained and I should call the AA. This I duly did and sure enough, the man from the AA confirmed that the battery was dead and got the car running again.

I've booked the car in for next week and intend to make an issue about this - I suspect, without having checked yet, that batteries won't be covered by the warranty. But surely it isn't right for a 2 month old battery to drain completely after 2 weeks? Has anyone else experienced this? Does it sound like something that "just happens"? Should I be insisting on a new battery at their cost?

Thanks for your help.

[WeeYari]

Same thing happens to a pair of new GM products my parents own. Whenever they go away for extended periods of time, they need to put a trickle charger on the battery. If they don't, after 2 weeks, they are dead.

[CTScott]

It would be interesting to see what the static current draw is for the 2012's with the smart entry system.

The 2nd generation Yaris (without smart entry) draws about 150 mA when powered off, which with its 45 Ah battery means that the battery will be down to 50% of its capacity (what is typically considered the safe discharge level for a lead acid battery) in 12.5 days.

[Geoff Peace]

Originally Posted by CTScott

It would be interesting to see what the static current draw is for the 2012's with the smart entry system.

The 2nd generation Yaris (without smart entry) draws about 150 mA when powered off, which with its 45 Ah battery means that the battery will be down to 50% of its capacity (what is typically considered the safe discharge level for a lead acid battery) in 12.5 days.

I do not understand this. 150mA is a very high figure for dark current, parasitic current, draw. At that rate it amounts to 3.6 amp hours per day! To 50% discharge a 45 amp hour battery this would take just over six days which is ridiculous. Surely there is a mistake here somewhere? I would be concerned if the draw was in excess of 20mA.

Regards Geoff Peace.

[Geoff Peace]

[QUOTE=RubySlippers33;644632]I have a 2 month old 12 plate Toyota Yaris T-Spirit with smart entry/start. I went on holiday for 2 weeks, leaving it in my garage and when I returned at the weekend, the car wouldn't start at all. It wasn't especially cold or anything like that while we were away. I 'phoned the dealership and described the "symptoms" and was told that it sounded like the battery had drained and I should call the AA. This I duly did and sure enough, the man from the AA confirmed that the battery was dead and got the car running again.

I've booked the car in for next week and intend to make an issue about this - I suspect, without having checked yet, that batteries won't be covered by the warranty. But surely it isn't right for a 2 month old battery to drain completely after 2 weeks? Has anyone else experienced this? Does it sound like something that "just happens"? Should I be insisting on a new battery at their cost?

Two months old! My Sunday bonnet! I would take it straight to the dealer, never mind booking it in. I would insist on written confirmation that the battery has not been damaged and also insist they find and rectify the problem. You have just bought a new car, why should you be expected to tolerate nonsense such as this? Please let me know how you get on with the dealer.

Regards Geoff Peace.

[CTScott]

Originally Posted by Geoff Peace

I do not understand this. 150mA is a very high figure for dark current, parasitic current, draw. At that rate it amounts to 3.6 amp hours per day! To 50% discharge a 45 amp hour battery this would take just over six days which is ridiculous. Surely there is a mistake here somewhere? I would be concerned if the draw was in excess of 20mA.

Regards Geoff Peace.

Unfortunately it is that high and I agree it is higher than I would expect/want it to be.

From and analysis I did a while back:


In doing some measuring of current draw of various things while the ignition is off I found the following to have the most significant draw while powered off:

ECM: 50mA
Body ECU: 100mA
Radio: 5mA
Clock: 5mA
Keyless Entry/Remote Starter on my 09: 150mA

[Geoff Peace]

Originally Posted by CTScott

Unfortunately it is that high and I agree it is higher than I would expect/want it to be.

From and analysis I did a while back:


In doing some measuring of current draw of various things while the ignition is off I found the following to have the most significant draw while powered off:

ECM: 50mA
Body ECU: 100mA
Radio: 5mA
Clock: 5mA
Keyless Entry/Remote Starter on my 09: 150mA

May I ask if your figures are based on one car or a larger sample?

Regards Geoff Peace.

[CTScott]

Originally Posted by Geoff Peace

May I ask if your figures are based on one car or a larger sample?

Regards Geoff Peace.

2 - The two pictured in my signature picture, which are an 08 and an 09.

[RubySlippers33]

Thanks guys. Unfortunately I can't get to the dealership until next Saturday and we all know what it's like pitching up on a Saturday without an appointment! So thought it would be easier to book it in. The general manager is apparently off this weekend but I will 'phone him again during the week and follow Geoff's advice. It's reassuring to know that I'm not the only one who thinks this is ridiculous! Will keep you updated.

[Geoff Peace]

Originally Posted by RubySlippers33

Thanks guys. Unfortunately I can't get to the dealership until next Saturday and we all know what it's like pitching up on a Saturday without an appointment! So thought it would be easier to book it in. The general manager is apparently off this weekend but I will 'phone him again during the week and follow Geoff's advice. It's reassuring to know that I'm not the only one who thinks this is ridiculous! Will keep you updated.

I would insist on knowing a few facts and figures. I would ask to see the relevant data in the manual if you are met with the 'Nanny knows best' or 'they are all like that' approach. 150 mA parasitic current draw just cannot be correct, everyone would have flat batteries at that rate! I am very interested in this one, please post the outcome.

Regards Geoff Peace.

[CTScott]

Originally Posted by Geoff Peace

I would insist on knowing a few facts and figures. I would ask to see the relevant data in the manual if you are met with the 'Nanny knows best' or 'they are all like that' approach. 150 mA parasitic current draw just cannot be correct, everyone would have flat batteries at that rate! I am very interested in this one, please post the outcome.

Regards Geoff Peace.

For anyone interested in measuring on their own car, all that is required is an ammeter. I remeasured both my 09 (with power doors and windows and remote start) as well as my 08 (with no power) using my clamp on ammeter.
I also measured my 2011 Tacoma for comparison, which with power everything, only draws 40 mA.

Here are pictures of the measurements:

09 with power package and remote starter (.15 = 150 mA):
09 Power and RS.jpg

08 no power: (.10 = 100 mA)
08 No Power.jpg

2011 Tacoma Pickup with power package (.04 = 40 mA):
2011 Tacoma.jpg