A couple of things. The NAH system is the same as on the Long Tested Prius. Sure they put it in a heavier car and placed the batter differently, but its still the same Hybrid System.

That being said, I doubt they are hiding anything. In order to get paid for Repair Work and Diagnosis time, they must submit invoices and that is recorded against the cars Vin. #

These cars are new to Nissan so I am not surprised that only one person is certified to touch it. When a battery drains down, it will cause major problems. It will screw with the computer system.

Finally, the NAH WILL re charge Hybrid battery when coasting down hill. Especially steep hills! I don't think it is a design flaw because then we all would be having the problem. I don;t doubt your problem, just think there is another reason behind it and not a design flaw.

 

Appreciate that explanation.

Now that I have my car back, I do see the recharging upon deceleration at highway speeds that you mentioned, however I also noticed that in some situations (coasting on level ground around 45 mpg or so there is NO charging present; and when I had the big problems with my car there was heavy charging all the time (thus the 26 mpg).

Interestingly, my batteries never got below 3/4 charged when I was having this problem. If the dealer indeed did nothing and the problem magically went away, I would expect that they could tell me that perhaps they had it disconnected the car from all power for x amount of time and possibly reset the computer, etc. As I mentioned, all of the radio presets were gone as were the user settings within the computer.

Just seemed strange that they would not tell me anything, refused to let me have a look at the diagnostics report and paperwork which was about 1/2" thick.

I guess we'll see how others make out. So far it's been 'replaced cell' or 'there is nothing wrong'.

 

I just got my car back from the dealership today after leaving it there all day yesterday. And they have said they could not find anything wrong with the car. I have noticed however that my car doesn't have any problems when I'm driving without the A/C on. But when I turn the A/C on, the same problems return with the high revving.

 

If you can reproduce the problem, all the better.

Take it back and have their certified tech come or a test drive with you (let him drive).

The Air Conditioning compressor is (I believe) battery powered on this vehicle, as opposed to being belt driving off a conventional gasoline engine, so it will place a higher draw on the electrical system overall.

Beyond that, I can't offer any advise, just waiting for mine to misbehave so I can go back and yell at the dealer again. After you get the car back the next time, you should call Nissan and log an incident, indicating that you have this problem that the dealer is somehow unable to diagnose and fix.

If enough of us call, they'll take the matter seriously and open up an incident to have engineering get involved. As I suspected before, there is a firmware bug someplace that either misbehaves when a sensor reads incorrectly, or a part that is failing within the electrical system and giving data that the computer cannot act upon in any civilized manner.

In such a case, a check engine light should illuminate and service codes logged so that when the dealer plugs in their computer, they can act upon it instead of coming up empty.

I'm a firmware programmer by trade and have been working in this field for 22 years. Believe me, something is amiss. Getting to it is the challenge. I predict a service bulletin but not for a while. The "computer gets confused" is not a good answer, it all comes down to error code logging and trap handling.

Problem is, there is no one place to list consumer cases like this (there are likely dozens of forums of disjointed and disenchanted owners). The splintered approach will never work and the dealers will not necessarily feedback concern to Nissan.

In addition, Corporate may not review the cases on a proactive basis and possibly does not have a procedure to monitor these types of incidents so do us all a favor and call Nissan and explain the situation in as accurate and clear terms as you can.

Not sure if Nissan is selling the hybrid next year based on Toyota technology or when their contract expires but if we do not get a solution, we are going to be in for years of pain.

 

Knowing Nissan's (not the dealers) record, I would bet that they as a company will assist you as long as you are in a position to receive it. In other words, don;t call or write them screaming and yelling, but rather tell them of this problem, print out this thread as proof of other identical issues and I am sure they will work to resolve it.

Keep this in mind with dealerships, ALL DEALERSHIPS:

The dealership makes money on Warranty Work. They bill the Mfg. There is a set number of hours for every problem, including unknown. Here is the catch. If I bring my car in for a tranny problem, the tech that gets that job assigned to him/her has let's say. 10 hours of billable work. If that tech does the job in 6 hours, he/she still GETS PAID for 10 hours! He can then turn around and with the remaining 4 hours, do another 2-4 hour job. So in 8 hours for the dealership, they just billed the mfg for 10-12 hours. Sure the tech gets his 10-12 hours pay too, but the dealership just made another 2-4 hours of billed work.

So where the Mfg, Nissan, might want to find and resolve the issue, to save them all the unnecessary billing they will ultimately have to pay for. I would bet that the dealership has not even reported this to Nissan. Why? Every time you bring it back, that billable time for them. Not all dealerships are this sneaky, but I know too many that are. The good ones are far and few between.

 

I put this on another forum and haven't got any answers yet, but this place looks more active/knowledgable. My dealer doesn't know how to do anything other than hook it up to the computer unfortunately, but this problem has me just thinking about selling the car. I've had the car a bit over a year and it has 12,400 miles, the problem has been going on for about 1000 miles.


My NAH has been acting wierd for the last three weeks. I guess I'm trying to see if anyone here has experienced the same issue because my dealer is clueless and of course it won't do it on the days I've taken it to them.

- When coasting down a hill, 3/4 battery charge, car warmed up, going well less than 42 miles per hour, the car will switch every 2 seconds between EV mode and the gas engine. Also, the car's brake won't work as well and the car lurches pretty badly. Street is smooth and the temps here are now 75-95 during the day. It's only done this about 3 times in the past three weeks. (dealer states this is normal, but I've had the car for over a year and this isn't normal)

- Recently the battery charge indicator on the left of the dash won't go very far into the blue charge area. In fact, exiting a hwy and getting on the brakes that used to bury the needle fully into the charge area, now barely moves the needle. It does this about every three days.

- The VDC light comes on and stays on for a few miles every once in a while. When the VDC light is on, I am experiencing the second problem above, but the VDC light isn't always on when this problem is happening.

- Gas mileage has decreased from mid 30's to upper 20's unless I have mostly hwy driving. No change in driving habits. We've had the car for over a year and driven in similar weather and it's never been even close to this low.

Thanks for looking and giving any imput you have.

Also, does anyone have any contact for Nissan corporate to see if maybe they have an answer. All my dealer knows how to do is hook it up to the computer and since there aren't any error codes, they say everything is normal.

 

To the previous poster...

I'm no expert on these cars, but it sounds like your batteries are getting too warm. I would look in the trunk, take the backing off in front of the batteries, and make sure there is air flow from the vent. The batteries are cooled from the vent behind the rear seats. Make sure nothing is blocking it. Perhaps there is a filter system which needs cleaning? The trunk lining can be removed pretty easily by pulling the center from the small round clips. Once the center is pulled, the clips can be removed. They can be re-installed by reversing this process.

Keep in mind the conditions which warm up the batteries.
1. Hot temps inside the cab
2. Fast charging
3. Fast discharging

VDC I assume means "Volts Direct Current", which may mean the 12V system. There are 2 DC/DC converters. One to charge the 12V battery. and one converts to 42VDC for power steering. Once again, if your 12V battery is having problems, it will overwork the DC/DC converter. One is located in the trunk with the batteries. If this is getting hot, chances are the batteries are too.

Personally I would throw a smart charger on the 12V battery. You may have to remove a cable to eliminate any draw on the battery for the charger to properly "read" the battery condition. I have already heard of several problems that were a direct result of a bad 12V battery. And one poster claimed that Nissan has a different replacement battery as a result.

ON EDIT: Well, when all else fails, RTFM. I looked and VDC stands for "vehicle dynamic control". One interesting thing that is in the owners manual.

"The light also comes on when the power of the 12V battery is reduced or the battery cable is disconnected."

 

Steve,

It does happen more when the temps outside get above 90, but it has also happened when the temps weren't even above 80 a couple times. If what you say is true, that could be part of our problem. We never have the vent covered though.

Another thing that confuses me is that we had the car all through last summer and the temps got just as high and this never happend once.

I really think we are a candidate for the replacement 12V, but the dealer said we don't have any service bulletins that apply to our VIN. I think he looked up recalls though.

I am going to take a printout of this thread as well as a printout of the service bulletin next time I take it in. It started doing this with 11,000 miles on it, and there's no reason for one of the 12V batteries to be bad yet unless it was just a dud in the first place.

Correct me if I'm wrong on this, but the two 12V batteries aren't the NiMH hybrid battery, but more like normal car batteries (even if they aren't quite normal car batteries).

Thanks for the response. I think my conclusion so far is that our 12V in the back is a dud and therefore the heat is really getting to it this summer more than normal. It's really unfortunate as this past month I have enjoyed driving the car like I used to.

 

There's only one 12V battery. It's in the trunk in the wheel well on the right side. It's a standard lead-acid type. I tried looking up information in this battery using the model # off the battery and did not get any hits. If I had to replace it, I might be tempted to use a deep cycle battery of the same dimensions.

But first things first, check the terminals for a loose connection! It may be that simple.

 

Thanks again. I thought about checking for loose connections, but was greated with the high voltage warning through the little access area in the right side of the trunk.

I never worried about tinkering with my motorcycle, but for some reason it's tough for me to take the plunge and mess around with the hybrid.

I'll try and look at that this weekend though. Seems like accessing the battery area from the trunk is easy enough.