I just found this TSB at the NHTSA site:

Make : NISSAN Model : ALTIMA HYBRID Year : 2008 Manufacturer : NISSAN NORTH AMERICA, INC. Service Bulletin Number : NTB08-044 Date of Bulletin : JUN 09, 2008 NHTSA Item Number : 10024942 Component : ELECTRICAL SYSTEM:BATTERY Summary :
2007-2008 ALTIMA HYBRID 12V BATTERY FOR SERVICE. *NJ

Anybody look into this yet?

Eph

 

http://x.nissanhelp.com/forums/Knowledgebase/links/341

You can access all the TSB's for the NAH at NissanHelp.com. You can register for free but are limited to one download per day or you can pay for unlimited downloads.

Edit - looks like they now allow two downloads per day for free.

 

****! I KNEW they should have been putting deep cycle 12V batteries in these things. This service bulletin is to replace you battery with an Optima battery.

 

new to this forum - lots of nifty tips here.

Sort of a dumb question, but what sort of symptoms should someone look for if the 12V battery is dying/dead? Obviously, in a conventional car, the car wouldn't start. In a hybrid, the HV system has me confused. As I understand it, the HV battery powers the AC and even the stereo (through a HV-to-DC converter). So, what does the 12 battery do? Start the ICE? Help the power windows go up and down? Is that it?

 

The 12V battery runs most of the normal accessories that it would in a non-hybrid such as radio, lights, horn, blower fans, coils for the ICE spark plugs, engine cooling fan, all the electronic control systems like emissions and ABS, etc. I guess a sign it would be failing would be these systems not working properly. You could always test the battery with a load tester(?) There is a device that steps down the 245V DC to 12V DC to charge the regular battery.

I believe there is no HV-to-DC converter as the HV battery is 245V DC. That voltage goes to inverters located above the transaxle where it is converted into AC and higher voltage for the traction motors. I also believe the AC compressor is run directly by the 245V DC - at least it has some big orange cables going to it which means don't touch.

 

Here's a more detailed discription from the First Responders Guide for the NAH about the electrics:

The Low voltage system:

A 245 volt DC, electric motor driven electric air conditioning compressor

 

thanks much, Lloyd! not sure why I thought the stereo was on HV-12V...must have misunderstood something I read elsewhere. Really appreciate the recap!

 

Took my car in this morning for the one year service maintenance and asked for this battery replacement. It did not show up on the recall list for my VIN number. He said that if it wasn't on the printout based on my VIN number that it does not apply to my vehicle.

 

It's not a recall. It's a service bulletin - meant to advise service techs. Basically it says that if the 12V battery ever goes bad, that it shouldn't be replaced with the same kind - but rather the updated model. Until your 12V battery goes bad, don't worry about it.

 

That is what they told me when I picked the car up. When the current battery dies, they will replace it with the different model.