Wow dude...that's a good read.

Of interest from this, we have a CD that's been stuck in the CD player for yeeeaaaarrrrrs now...funny that's near the top of the list. This reading just reminded me of that. My question on this however would be; if this were possibly the culprit, why does it happen randomly and about a month between occurrences?? If it were trying to kick out that CD, wouldn't you expet it to happen almost daily?

**Update**. Battery reads 5.0 volts tonight and will not take a charge from my charger. It's a Battery Tender Jr, so I'm guessing the voltage is too low for the charger to even start; but that's just a random, educated guess as I know the charger is good.

 

2 thoughts here.

1. The battery was not the best to start with, making the previous symptoms seem like current symptoms.

2. The issue causing the battery drain, drain cycled to the battery took many times killing it.
- A battery will only take being drain so many times before it won't take a charge again.

If the battery is at 5 v and the charger won't start, there is something else wrong with the battery / connections, the charger should work down to 3 VDC.
- What is the led states ? ( color and flashing or not ).

 

Actually considered this but unsure how to completely rule it out; besides buying another batt. It's a brand new Optima. Bought in Jan, manufactured in Dec '12. Never had bad luck with Optima, but it's possible to get a bad anything.

This is the first and only time this new batt has been cycled to dead, or to a point it wouldn't start the car...but I understand that theory.

Yea, but I don't know what. Charger is all connected good.

With charger plugged in and connected well, the LED on the charger is flashing red. That indicates its it's not doing anything; basically.

 

1. Ain't flaming ya but Optima has been junk ever since Johnson Controls bought them out.

2. Optimas require a specific charging cycle due to their agm construction. Make sure your charger is rated to charge agm batteries.

3. Battery tenders usually take awhile to bring an agm battery up to full charge.

 

The way to rule it out was to have it load tested.

Hard to say if the test would show anything other than dead now that it is at 5 VDC and won't take a charge and has been full discharged so many times.
Time is past testing if it was the battery or not.

A battery that has a no load resting voltage of 11.4 is considered fully discharged.
Cycling a battery between 12.7 to 12.3 VDC is considered normal.
Cycling a battery down to 12.2 VDC is OK, but will start to shorten the life of the battery.
Cycling below 11.5 V is not recommended and will greatly reduce the life of the battery.
- Does not matter if it will start an engine or not, that is a different question.

A number of times to full discharge will kill a battery dead ( and every time it is full discharge shortens the life of it - hockey stick progression).

This is what I am getting at with load testing it now is going to show dead battery. If the battery will or won't start an engine is not a diagnostic test point.

The owners manual for your charger shows this as :
This could also be an issue with the posts internal to the battery or damaged leads on the charger, given you measured the battery voltage at 5 VDC.

Get your receipt and return the battery for an exchange.
If you have the same symptoms again, next time you get 2 reading below 11.4, take the battery in to be load tested vs letting it go on.

Also, get the radio out and get the CD out of it.
I do not know how the stereo in a Lexus works, there could be a attempt time with the eject and it resets and attempts it again later and continues until it is out ??
Need to remove this as a diagnostic step, best to do it before installing a new battery.

What you have now is dead, can't do any other diagnoses with it.

 

SSCULLY...thanks for all the awesome info dude!! I'll be bookmarking this page for future reference!

I just wanted to jump back in and update you guys for taking the time to help. Turns out it was the alternator. Still seems like extremely strange symptoms for an alternator problem, but whatever. Got it started and took it to the shop to test the alternator. Turns out, the alternator was only putting out ~30 amps, and only 12.2 volts. Gonna swap it out and see what happens.

 

Steve, your post is spot on, excellent info. There is one FYI that I have learned by experience. If a battery is sulfated from being run down (even to 0.0V) and was a reasonably strong battery (time since new figures in no matter how strong before sulfation) before it was left to discharge and sulfate, it CAN be brought back. I have done it numerous times. On 2 batteries just recently. My neighbor has 2 Beemers that he hadn't driven for well over a year. I knew the batteries would be completely sulfated. They both tested 0.0V and 0 CCA's I did what I always do and left them each on my 40A shop charger for about 3 days. The 3 year old 925CCA battery came back to about 12.75V (actually went to about 13.4V then settled at 12.75V after Load test) and about 875 CCA's. The 560 CCA 5 year old battery came back to about the same voltage but topped out at about 245 CCA's. 3 days for each. They will stay at zero amps charge for possibly a full day or more before they start to come back. The 560 CCA battery actually turned the 528 over for about 20-25 seconds at full strength before we realized it was out of gas. When we put gas in it started and quickly ran like a champ. I learned this by accident many years ago and have used it quite a few times since, always successfully. I always watch battery temp and have found in the sulfated situations, the temp doesn't rise even at full charge for 3 8-10 hour days. Interestingly, my brother told me a number of years ago that a mechanic at a L-M dealer he worked at told him the same thing about charging a totally sulfated battery.

 

Well...2 months have passed since installing a new alternator and the gremlin is back! Driving along fine, sat in the garage over night, and dead again!

 

I am been thinking this one over since you posted yesterday, and I got nothing specific with a new battery and new alternator.

This last battery, did you go with an AGM battery again ?

New alternator, and the time being 2 to 5 months without issue is going to be hard to pin point, so I am tossing out SWAGs.

Did you ever get the stuck CD out ?
- Don't know in the 2 to 5 months if the CD option was selected on the audio unit and it is still trying to eject that stuck unit.

Did you happen to get a VDC reading the AM it was dead ?
- Just curious if it was back down to 4 VDC again.

Time to have the alternator tested again if your BT Jr will revive it.
Could be the charging controls ( i.e. PCM on the F150 ) is causing an issue with the output, which could point to another source.

Anything like a DC power point to USB adapter left plugged in ?
- anything else aside from this that is not a modification, just something added in ?

Again, I am at the SWAG stage with the infrequency of the issue.

 

Thanks for the help again scully. Just as an FYI for you, I have not had the opportunity to run the items posted by 88Racing back in post #15. I don't know what the heck is up with this thing. I would think it'll be futile to pay a shop to troubleshoot it. Seems you'd be chasing a ghost; the problem is clearly not active all the time or else I'd think it would die every night.

Yes; another Optima Red Top; have always had great luck with them. These sypmtoms are unchanged between the old and the new battery...but that's been mentioned.

CD still stuck. We don't ever select the CD player because it's a known.


No reading this time. I'm out of town and unable to do anything for a while.


Didn't put it on a charger this time. Wife had to jump start it. Jump starts just fine and like with every other occurrence, it works just fine for weeks...until the next time, LOL!


No mods to the car and don't believe anything is being left on; not intentionally anyways. Phone charger plugged in, but the aux outlet is not hot when the car is off.


What is SWAG?

 

Scientific Wild Arse Guess

As opposed to a WAG!

 

How do the battery cables and grounds look?

I've seen cars not start, and you install a star washer in the battery post of the starter (washer cuts new contact points) and they crank right up. I realise this isnt your symptom, just talking out loud again.

Does your symptom have any notable frequency? Like after driving at night, or in the rain, after openning the trunk etc ??

 

Or also could be a FRED issue F'n Redicolous Electronic Device

 

I thought that was limited to GM products and anything with Lucas Electric!

 

No need to send you to the optometrist, you're seein' 20:20.