12v battery - is it time to change?

Yeah I would go with your #1: connect a digital volt meter, either at the jump-start point under the (erh) bonnet, or directly at the battery, to see where you stand. Anything under 12.3~12.4 volts, it's near-dead. And assuming it's the original battery, time for replacement. £115 seems reasonable, installed.

 

congrats and welcome!
test it after the car has been off a few hours, to remove surface charge. all the best!

 

Regarding question 4, unless the battery was on a list of items to be checked, my answer would be "no". If you are lucky a visual inspection might have been performed looking for corrosion on the terminals.

 

check the 12v, or the hybrid battery? and if it is the 12v, does that service mean they will replace anything they find bad for free? or would you have had to pay for a new 12v?

 

i understand that you checked the 12v, but i'm asking if they checked the 12v, or the hybrid battery.

that's a good deal, but how do you prove it didn't go bad after they checked it, shouldn't there be a spec on their report?

 

interesting, it's amazing the car even starts at that voltage. where do we go from here?

 

Time for a new AuxBattery! Normal life is around 4 to 5 years! Failing/dead AuxBattery can cause all sorts of other problems which on the face of it, might not be obviously related to 12V. Replace battery and other problems might disappear! Good luck!

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Do you really want to take that on?

Two weeks in, you may have a case. Maybe give it a try. Maybe agree to 50/50? Was this private purchase, or through dealership, with some sort of warranty?

Dealership service departments say they check everything, reality is somewhere between what they claim to have done, and nothing. Worst case: they just are checking a lot of boxes without doing anything.

Regardless of their responsibility to check the OEM battery, it is a "consumable", ie: something the owner is responsible for replacing. Sometimes replacement batteries come with warranties, Toyota USA for one, but I'd suspect they're pro-rated, and debatable: it's just too easy to run a battery down. And regardless, batteries last 4~6 years.

Someone in the UK just yesterday said they were quoted around 110 euros, for a new installed battery. That's reasonable.

12v battery - is it time to change? | PriusChat

^ Hah, that's you, lol.

Oy vey, I'd stand by my earlier advice, in your other thread. Just get a new battery, they're offering a good deal.

 

if you're sure everything is off when you're getting that voltage, i would replace it.
there is no warning message, just go/no go. some people get lucky, and the car starts doing weird things like not unlocking doors or getting dash lights. that gives them time to replace it without getting stuck.
i'm surprised you're not having any issues.

 

(Just happened across this thread while passing by for something else.)
If I recall correctly then I read something previously about the auxiliary battery mostly being used just to start the inverter - at which point your power comes from the hybrid battery anyway, so there's plenty of it.

I don't recall the whole story, but I think my 07 reg gave me a clue that the battery was going bad across the 2015/2016 winter when it refused to start after I hadn't used it for a week. I'd seen reports of problems here but it was no issue through the summer and the (local independent) garage ran a load test and said the battery seemed fine.

The day our first cold spell of winter 2016 hit I'd parked the car in the work car park. It wasn't much fun to find the car wouldn't start in the cold and dark evening.

I'd get the battery replaced before winter comes, if I were you.

(Also: When you've connected up the jump leads and got some power to the car but the MFD display says something along the lines of "there's no way you're driving this car!"... do at least try to stick it in gear and drive it.)

I looked at the various battery options and couldn't find anything more sensible or economical than getting the battery from Toyota. (With the yellow-top you have to faff around with tubes that don't fit, as I recall.) I saved myself £15 by buying the battery as a spare part and fitting it myself as a matter of principle. It's a bit more awkward to fit than you'd hope though.

However, if you do fit it yourself then it wouldn't surprise me if, on a 2006, you discover that there's water in the battery well and you need to drain that and then reseal the hairline cracks up in the roof gutters if you don't want ice on the inside in the cold weather.

(You're only seeing my car's bad side. Most of the time it's lovely. Also, my computer almost always says 50 - 51 mpg over a tankful of petrol. Doesn't seem to matter whether I'm doing in-town or motorway trips. Air-con almost always on... which reminds me, that needs a regas.... :-( )

Good luck!

 

sorry we missed this vicky, how did you make out?

 

congrats! i hope that wraps it up. and a testament against those who claim a bad 12v cannot effect fuel economy.

 

Glad it's fixed. I just now saw this thread for the 1st time. As Bisco said, this really shows how hard the car can be working to keep a bad 12V battery charged.