I have a 2012 QX56 w/ 56K miles. The car has not started (or hesitated) twice now in the morning. I come from an automotive background so I've performed the necessary diagnosis (multi meter, load tester, current draw.) Battery seems to be ok but I noticed that the alternator runs at 14.4v at initial startup then drops to 13v within 30 seconds. At 13 volts charging- I just don't think the car ever has the opportunity to catch up after driving all day. My wife gets home with a battery in questionable shape (not fully charged from driving) then the car sits for 12 hours with the usual drain of the clock, radio, ECM, etc. I'm thinking this is why it has problems in the morning. What does the alternator use for voltage regulation on the QX56 - surely its not just a standard regulator?
Alternator Issues - Drops to 13v When Running
- Thread starter aebarto11
- Start date
pjdavep
Active member
Check post 50 and 56 in this thread:
http://infinitiforum.net/infiniti-forum/showthread.php?t=12436
You may be able to cut a wire, or maybe you need a new alternator, but as you'll see from the other posts in that thread, the Infiniti supplied battery is not up to the task of keeping up with a fully loaded QX.
Later,
pjdavep
http://infinitiforum.net/infiniti-forum/showthread.php?t=12436
You may be able to cut a wire, or maybe you need a new alternator, but as you'll see from the other posts in that thread, the Infiniti supplied battery is not up to the task of keeping up with a fully loaded QX.
Later,
pjdavep
drewdogg808
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I noticed the same thing for years on my 2011, which is probably why I've gone through 5-6 batteries. The last fix must have updated software or something else, because the gauge no longer goes up and down and stays at 14v. The alternator never tests bad, but I've read that it was programmed that way to save mileage? The long battery thread has people mentioning the battery is not up to par, but I've always thought it was something else.
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marctronixx
Staff member
poor grounding points (there are 3 i believe), faulty battery cables, faulty regulator, faulty alternator, something is causing a slow drain on the charging system.
So what's the "official" voltage that we should be seeing on the QX? Mine has always had issues with the battery (leave the doors open to vacuum it out? dead battery), so, after reading these posts, I opened up torque and connected to the bluetooth OBDII adapter while driving last night. Over a 30 minute drive (15 minutes both ways), the voltage at the control module settled at 12.4 volts on the front half, and a little over 13.2 on the drive back. My QX is fully loaded, so (based on these comments) I'm thinking I should be seeing more like 14v. What's the general consensus on "the fix"? I want to make sure I'm asking my dealer for the correct resolution.
Thanks
Thanks
marctronixx
Staff member
14 for sure at cold startup and/or if car has been sitting for some time.
usual driving it fluctuates based on electrical load, but should not be 14 volts all the time, more like around the 13 volt range. 12 is just too low to maintain a good supply of juice to the battery given the electronics on these cars. ive a fully loaded one as well.
you could have worn out cables (not just the battery connectors, but going to the alternator and grounding strap) or a fulty battery. i have an odyssey battery and that thing is bullet proof.
usual driving it fluctuates based on electrical load, but should not be 14 volts all the time, more like around the 13 volt range. 12 is just too low to maintain a good supply of juice to the battery given the electronics on these cars. ive a fully loaded one as well.
you could have worn out cables (not just the battery connectors, but going to the alternator and grounding strap) or a fulty battery. i have an odyssey battery and that thing is bullet proof.
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G
G-316617
voltage should be 13.5v-14.5 on qx56.
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