12V Battery

[korat102]

I had the dreaded red triangle on startup this morning. Went out after a second. Checked Battery voltage when I got home. 10.6v on the Battery terminals! !Removed! odd since I charged it only a couple of weeks ago. Admittedly I haven't used it much except for half a dozen very short journeys recently but even so... Hope my Optima yellowtop isn't getting tired already...

Anyway, thought I'd check the charging voltage when I had it running. It's a rock solid 14.0v at the Battery terminals.

It's sitting in the garage on charge (via the mains) now. I'll keep an eye on things over the next few days...

[timberwolf]

How long have you had the Optima YT?

[korat102]

I fitted it to the Prius 28 months ago. To be honest I don't really use the car enough to keep an optima charged. I really need to put it on that maintenance charge more often. I've looked around on that there internet thingy and discovered that these Optima's can take a long time to charge properly even after the chargers think they're done. Anyway, it's been charging for a couple of days, I'll leave it today since I don't need the car at the moment and see what it's like on Saturday.

I'd quite like to swap the thing for a RAV4 but the choices seem to be an older one where the rear door only opens half way or a newer one without a spare wheel. Think someone at Toyota needs a slap with a wet kipper.

[timberwolf]

My usage is also low. If the Optima Battery is going to fail after only two years it probably is not worth the higher cost. I thought about getting one because of the claimed deep discharge and longer life but I did not find any information about the life span if the Battery was usually undercharged as would be the case in a car left parked for a week at a time.

[korat102]

It's not looking good. After charging three days with a CTEK charger which is supposed to be able to cope with these things, the voltage started dropping as soon as I disconnected the charger (with the Battery isolated). Within a couple of hours it had dropped to 11.8 volts. After a day it's down to 10.5.

I have a Bosch S4 on order since I'm in no hurry. When that's fitted, I'll try charging that yellowtop again for a week or so and see what happens. From what I've seen on the internet and from my own experience, I'd say the yellowtop is not going to be worthwhile for low usage vehicles.

[timberwolf]

Doesn't sound good. Did the Optima last 2x longer than the OEM Battery?

Is it possible that you were just unlucky, and the Optima has failed mechanically i.e. due to a fault in manufacturing?

I seem to recall that the Battery voltage is dependent on the ambient temperature and that the 12.8V is usually quoted for 20C. I can't recall off the top of my head how much the capacity typically reduces by per 0.1V for how many degrees C. I don't think it would account for your Battery reaching 10.5V in a day though.

[MLW2233]

Given the cost of the Optima that is a bit worrying. I've been two weeks now on the new Bosch S4 (you can get them from Europarts on the spot, but at a discount if pre-ordered on the website) and all is very well. We don't use the car much, and it can go 3-4 days with no use at all, but all the dash and central locking' irregularities' have disappeared and the car has 'gone back to normal'.

When ever the old Battery was weak, the central looking would have a soft clonk clonk sound as the locking and immobilister were set.

After the new Battery, it is back to the old hard strong clonk clonk sound. Quite reasuring really.

[korat102]

It's certainly possible that I had a bad one, there's no way to tell except putting it on a longer term charge and seeing if it recovers. I'll consider doing that but the way the voltage dropped in the Optima over such a short period I have a feeling I'll be wasting my time...not to mention the electricity.

The original Battery lasted over five years. The Optima didn't manage half that. To be fair to the Optima though, the operating conditions were completely different so it's difficult to make a meaningful comparison.

The first five years, the car was used a couple of times every day. In the last few years, it's been used a couple of times a week. Sometimes it's sat untouched for two, occasionally even three, weeks.

I would have hoped for a longer life but they don't like sitting partially charged like that...maybe there's a lesson there - check the Battery every week and if the voltage is low (below 12.4v or so) put it on charge!

[MLW2233]

What is the Optima guarentee? The Bosch one is 4 years.

[korat102]

The yellowtop has a 2 year warranty. Inevitably it lasted just over that time.

If what you read on the internet is correct, it seems that modern day Optima batteries are made in Mexico and are not a patch on the older ones...

[Ancient Nerd]

It is hard to see any logic in buying the Optima rather than either a Toyota or Bosch Battery. The Toyota Battery looks good for at least 4-5 years, and I am sure the Bosch will last at least as long.

This means that you will need to keep the car for at least an extra 7-8 years compared with the Toyota Battery or 9-10 years compared with the Bosch, to make it worthwhile buying an Optima. This is assuming that the Optima will last for that time.

Even with the need to keep the car a lot longer because of the extra depreciation resulting from the Weasel Warranty, I'm not planning to keep it that long. So I cannot justify the cost when my 12 volt battery eventually dies. The Bosch looks like the best buy.

Also the warranties say a great deal:

Bosch 4 years

Toyota 3 years

Optima 2 years.

[MLW2233]

I think that sums it up nicely.

I've had Bosch batteries before and they just ooze quality, could start a train. About 5 years ago there was a period when they were guaranteed for life! This later reverted to 4 years. As mine was about £51 with discount, why go elsewhere?.

[Jellyb]

After several "Electronic Park Brake Failure" warnings, usually after sitting in the car with the taxi data and radio on for over 45 mins, I trawled the forums for advice. I was surprised to see many mentions of unusual electrical problems usually blamed on the 12v Battery starting to fail. I had the Battery checked and confirmed it was on its way out. My garage checked with a motor factor co for a price on a replacement, £120 + vat. I got them to price up a Toyota original which came in at £90 inc vat, happy with that.

No problems to report since fitting.

The original Battery lasted 201000 miles over 5 years 8 months which is phenomenal in my job. In 24 years working I've had to replace the battery every year until I bought my Prius.

[PeteB]

FWIIW - my last Gen 1 Prius had a new Battery (under warranty) in 2002 when it was a few months old, and it was still going strong when I sold the car 9 years and 160,000 miles later!