I bought a Toyota 800A battery for my 2006 Lexus IS220D only 8 months ago. I do nothing but motorway/highway driving on that car 4 times a week @ 60 miles per trip. It's been (slightly) hard starting recently so I left it for a week. Didn't bother to start the car, just tested the battery and it was 0/0 SOH SOC.
My theory:
1. the car had a garbage battery in it when I bought it and it's damaged the alternator.
2. 8 months old batteries from Toyota can't stand the cold for 1 week and die.
3. I've got a parasitic drain.
The thing is I charged it for 6 hours yesterday and it went to 80/98 SOH SOC, and I went back today to charge it again and it's dropping from 80 to 65 SOH as I charge it. I did the same thing with a Varta battery (that stood for 3 years) and got it up to the 90s. So do you think I damaged the battery (should have left it at 80) or is it garbage?.
Forgot to mention the battery was 100/98 new.
Thanks.
Don’t Toyota batteries have a 84 months warranty?
After charging - I’d test it with a battery tester. If the tester says the battery is bad, I’d go in and request a warranty replacement.
check that the alternator is supplying the correct values. (~14V)
With a replacement battery, check what’s the draw using an AMP clamp once your cars computers go to sleep - to check if there’s a drain.
Well you can get broken worn out parts even when they're brand new if they weren't made correctly. Have a guy like me a professional mechanic load test the battery he can tell you whether it's good or not
It's not the battery, it's the alternator and/or parasitic drain.
Much appreciate the reply @scottykilmer @Dan and @Doc The battery is currently charging over 60% and is at 74%. I thought only old batteries took this long to charge. I noticed from Scotty's videos that he uses 1ohm 10Watt resistors when testing for drains and resetting the computer. So I'll get one of those and a voltmeter to test for a drain. I've got a battery tester.
Might start another thread on recommended Voltmeter makes that arn't Chinese if that's alright?. So far only found these guys: (link deleted, didn't work) 'Kaiweets' is the make.
You can get the resistors from Amazon for a few pence, but I don't really trust them. Problem is they've destroyed the UK market, so even if you buy a quality resistor from a UK make (assuming it is) at about £7.50 each, they add on a handling charge @£25 and shipping at £15. But I suppose £40/50 is worth the peace of mind...
Why use a resistor when you can use an AMP clamp? It’s just simpler.
And yep, a thread on what’s a good voltmeter for car repair could be great, I don’t think recommends one - but it’d be a good idea to check “tools” first.
@dan DC current clamp meters are very expensive, and they don't measure small currents very precisely.
Ordinary multimeters are much more affordable and sensitive in the mA range.
Thanks again gents, I'll do some reseach on some tools and go ahead.