tomscot2 - thanks for the feedback..i too never had an issue in the past with disconnecting- connecting 12V, and its hard to believe re-connecting a 12V battery could cause any catastrophic issues. The other odd thing was the warning lights did go off initially but they returned several hours later that same day.

 

Steve - I will hit O'reilly and followup asap. Rgds

 

You're very fixated on the 12V. It has nothing to do with the disconnection of the 12V battery. Disconnecting the 12V battery likely prevented you from having to replace the 12V as it likely would be damaged after being connected for 4 months.

In most cases, you can't leave a 10 year old hybrid with a deteriorated pack parked for 4 months. The cells discharge. If they discharge low enough and dwell there for a long enough time, they become irreparably damaged. When you disconnected and reconnected the 12V, the car registered voltage fluctuations on the 17 blocks at startup (about 30A load) and coded. Even a few moments of charging are enough to float that voltage into the working range. You disconnected the 12V, reset the codes, and the next time you tried to start, the blocks were less wonky.

However, after several miles of driving, the car again sensed wild fluctuations in the block voltages due to one or more failed cells when loading and charging the battery during the normal course of driving.

Given that you've left the car sitting for extended periods of time before, and you've seen this behavior before, a battery failure is almost a certainty. The difference between this time and the last time was your battery didn't self-discharge to the same degree.

I could be wrong, but I've seen this happen a dozen times after shorter storage periods. The most recent was a 2008 Prius that sat for 3 weeks. TWELVE out of the 28 modules had failed cells. Worst I've ever seen.

Given Nissan's ridiculous pricing for that pack, I hope it's not the case.

 

Steve- thanks yet again for discharging more info..in-between tonight and when I can make time for O'Reilly,i just hope the car will continue to operate.

 

The larger engine of the Altima/Camry vs. the Prius makes them operate reasonably reliably even on a totally failed battery.

Risks of driving on a failed battery:
1) voltage may drop so low, can't start ICE.
2) in rare cases, 12V charging may not function.
3) Hydrogen explosion. Repeated charge/discharge of a failed cell causes it to generate hydrogen and oxygen and heat. I've never seen it happen with Altima/Camry, but it's common for a Prius if you drive on it for too long.

#3 is basically a gunshot as the one cell blows its top. You will crap your pants a little, but the car will continue to run until you turn it off. You should get to a safe place ASAP.

 

I see..the gunshot scenario sounds freaky - I hope I have atleast a few days till I can take proper time off to get over to Orielly's. Its actually very unfortunate for me because the car just passed the 150K mileage threshold (151K and change) because Nissan would still have it under warranty up to 150K...anyway, lets hope its not something major with the battery because otherwise I wont afford to fork over 3-4K on a battery. Will cut my losses and do without a car for a while.


Hybrid ? Never again..

 

Again, never seen or heard of it happening on a Camry/Altima.

For your sake, I hope I'm wrong about the battery.

If it is, I would vigorously encourage you to pursue a goodwill warranty claim. toyota frequently gives concessions to folks who are just outside the warranty, or in on one and way out on the other.

$3200 batteries installed for $500-1800 in my experience.

Are you in California? If so, what area?

 

I'm in Oakland, but I've had a rough time dealing with my local Nissan "stealership", they tried to fleece me about 6 months ago on an unrelated issue that forced me to take it to a dealer, I'd rather go to another Nissan like in Richmond or Hayward etc. Why does it make any difference if one's from Cali ?

 

By fleece I mean I took the car in for a job they PROMISED would resolve my issue - only to turn around and tell me they overlooked something else and it now would cost me $12,00 after I brought the car in for a $400 job.

 

typo - $1,200.