Im in canada and its starting to get cold
I didn't drive my car yesterday and when I did today the battery was on the last notch when I started it and it struggled a bit to get going
then it goes back to normal instantly as expected.
Im worried if I leave it for two days I will need a boost
I left it for 4 days last year and needed a boost
I had lexus check it and they said it was fine
this isnt normal
Im just curious how the other canadian isf's behave
any input?

i also have the electronic corrosion control module from sym tech
that of which I'm a skeptic
maybe that could be the culprit but i doubt it because i don't imagine it using that much power

 

Try cleaning the terminal connections and sealing them with di-electric grease (silicone).

You can have your battery tested at a parts store - sort of a second opinion. The dealer might be saying it's "fine" even though it's not as healthy as it once was to avoid a warranty replacement.

Your other options are a battery tender or replacing the battery.

How old is it? Batteries last 3-5 years or 300 full cycles.

 

its a 08 isf 1749
didn't pick it up until april 09 though

 

I store my F for the winter. Last year I made the mistake of not disconnecting the negative terminal from the battery. 4 months later when i picked it up the battery was so dead I had to buy a new one. I would charge off another battery but it wouldnt last long. Pretty much the same problems your having.. I never take my battery to get tested. I just use my voltmeter to check the charging level. A brand new battery should be peaking at around 16.5 volts. If your at or below 12 consistently your battery is a goner..

 

In just shy of 40 years working with electronics, I've never seen any lead acid 6 cell battery make more than 12.7 volts - new or used. If you're seeing this much voltage with a decent (not $10) VM, there's something very wrong - it defies all physics. It's also meaningless. If you want to know how good your battery is, measure the voltage under load. You could have a badly shorted cell and still read full voltage until you put it under load, then the bad cell will completely drop out.

What the OP is experiencing is sulfation. It's what slowly kills batteries over time. There are ways to prevent and reverse sulfation, but they're difficult to justify for single battery owners.

 

So your saying its sulfation that killed our batteries? I thought it was the slow drain on the battery plus the fact that it was obviously never started in 4 months so the battery never had a chance to charge. I didn't notice any white powdery stuff on the terminals--it looked mint. Like I said though it wouldn't hold a charge for more than a day. I must be thinking of the charge the battery is showing while the car is running... Will unhooking the terminals prevent the sulfation or should I just start the thing for 5 minutes once a week...

 

i'm in Calgary Alberta and i didnt have any issues with my F in -30 weather last year. -40 she gave me the grrr rrr rrr before starting, but fired right up afterwards.

 

Oh i sure did. I got stuck in a snow bank and 15 minutes later when i got out my engine undercover was shredded. Im still driving without it. Its actually the salt that stops me from driving here in the winter. They use soo much salt in toronto that it just rusts your car to **** .I assume your getting your car sprayed each winter...

 

my car hibernates for the winter
its just the cold days leading up to and after the snow that sucks the life out of the battery
I couldn't let it sit for 2 days or id be worried id need a boost
sort of a hassle but ill cry to lexus in the new year/next service and see what they can do

 

should really get a battery tender if you are going to store your car

 

i have one
I'm just talking about leaving it for two days here and there
and i shouldn't need one for that

 

LOL where did that guy get his info from ......16.5v on a stock alternator and stock battery? NO WAY NO HOW. Resting should be 12.6-12.8v on a stock battery and with the car running around 13.8 -14.xx volts.

if you lived closer (the o.p.) i would give you my stock battery since i am getting ready to rip mine out and run an XS Power battery instead.

 

nope, never sprayed. But I wash my car down all the time, and park in heated underground. (which can actually increase the rate of corrosion)

 

haha, thanks I appreciate that
but I'm hoping lexus will give me a battery once i have a good cry

 

Yep, that's been my experience too. And, if the F had a darn Voltmeter in the cluster we could keep track. I added a Voltmeter and Oil Pressure gauge to my last car, a G35 Coupe, pict attached. I wish I could do it with the F Or, maybe the car should have come with those two gauges from the factory, ya think

Lou