Still getting 12V error with new 12V battery

[danbertolet]

Thanks Gerry.

Any recommendations for how to track down the ground fault?

Is it time for me to give up and bring it to a dealer repair shop?

[LeftieBiker]

You can also just link images here inline, so that they appear here, using the "Img" tag in the editing tools.

[GerryAZ]

Do you have any paperwork for the traction battery replacement? If it were mine, I would discuss the situation with the dealer that did the battery replacement to see if there is any remaining warranty. If not, then I would systematically check all auxiliary systems that use traction battery voltage (heater, heat pump or A/C compressor, onboard charger, and inverter/motor) before going further. There are hazardous voltages involved in all of this testing so I am not advocating DIY unless you are qualified. Unless there are problems in the auxiliary systems, the ground fault is likely inside the battery case or being caused by faulty ground fault sensors.

[nlspace]

Do you have a voltmeter? If so then it might help to monitor the aux battery voltage before and after starting to determine if you are having issues from a weak or worn out aux battery causing this fault.

A sulfated battery can read a high unloaded voltage but will collapse under load, and it will not accept a normal charge. Just because it is a "new" battery doesn't mean anything if it was left discharged, even 3 days is enough to cause permanent sulfation damage. There is plenty of information about this on the wwweb.

[danbertolet]

nlspace - Right now the 12V reads 12.2V with the car off, and 11.8V with it on.

See also the linked LEAFspy screen shot from yesterday showing that it's drawing 7 amps, which seems like a lot of current for the car on but no accessories running.

http://citytank.org/images/IMG_5823.png

But based on GerryAZ's above response that the error codes indicate a ground fault, it doesn't seem like a weak battery is the root problem. In fact, I wonder if the 7A draw on the 12V is related to the ground fault?

[cje]

See ALLDATA.com for info on how to isolate a insulation fault in the high voltage system.
Suspects are wiring/connectors/compressor/heater/PDM/traction motor.
Not a normal DIY as has been said.
Let us know what you come up with.

[alozzy]

If you know first hand of a trustworthy Nissan dealership that has certified LEAF mechanics, then hopefully they'll figure out the root cause.

Another option might be this company:

https://www.ev-works.com/contact/

Having said that, I haven't used them before so this isn't an endorsement. Check them out before giving them a call...