[Edit: Replaced the 12-volt battery to solve this]
Need some advice--for a 2012 SL with 45k miles and 8 capacity bars, here's my troubleshooting notes and observations:
The car has been garage-kept until August 2019. Then the owner left it outside fully charged for several weeks, and then it wouldn't start. Called tow service and they came and jump-started it showing 19 miles range. Then towed it to the dealer service.
Dealer checked the 12-Volt aux battery reading 435 CCA of 500 on the label and declared it good. Chargged the pack overnight and in the morning started it and showed 19 miles range, and declared the HV pack as bad. Towed the car back to the owner and that's when i was given the car for troubleshooting.
Used LeafSpy: showed 42.8 Ahr and the pack was at 401 with all cells within 10mV, but dash only showed 7 chargge bars and 19 miles. Drove it 20 miles to home and it dropped to 4 bars with 21 miles Range Remaining. Spy showed the Aux battery at 14 V after starting with taper down to 13 V, 2.5 A while driving.
The 12-Volt battery had been replaced at the dealer in march 2017 and it was reading about 12.5 OCV with -0.3A draw, so i chargged it out of the car overnight at 3A. Added some distilled water to cell #1 and chargged again at 1A. Measured with a 100A tester and it showed as good at just below the 600 CCA mark. Specific gravity measurement read weak at 1.12, so trickle chargged at 1A till it hit 14 V.
Chargged the pack using L2 to 12 bars 55 miles, and drove it 40 miles, then repeated and next day drove it 50 miles with 9 RR. On the third day it would not go to READY, the RR and bars were blank, with yellow PS and ! errors lit up. Jump start failed. Aux reading 12.6 OCV.
Removed the aux to measure OCV and trickle it. Then shorted the positive and negative cable lugs together before putting Aux back in. Cars started to READY showing 11 bars and 44 RR, so i drove it 40 miles down to 3 bars. Chargged L2 overnight and same failure to start the next morning, quickly unbolted aux cables and shorted them together, and re-install. Started to READY showing 7 bars and 41 RR, drove it 42 miles and showing 2 bars and 12 RR... What is goin' on with this thang?
The 12V has about 0.25 A draw all the time, so in 4 hours it pulls 1 A-Hr out of the aux battery. This is a Nissan 51R battery, 500 CCA, any idea what is the capacity?
It seems that shorting the lugs somehow resets an error condition--any ideas if this is really a thing or just coincidence?
Spy was showing 12.0V, -7 A draw while the car was just sitting in ACCY mode. Is this normal draw? How much does it draw during the start transient to go to READY mode?
Tonight when i plugged in L2, the voltage on the aux went up to ~14.2, +11 Amps, then it slower tapered down to about 13.13 V and +1.5 to 2 Amps.
i know that a weak, old or worn out aux battery can cause a multitude of issues on EVs.
Earlier in the week i took the 12-Volt battery to the dealer with the invoice to see about getting a replacement under the 84-month warranty, but they said it had to be in the car, and the car had to be brought to the service dept and tested there to determine if good or bad. At the time i couldn't get the car started, so kinda hard to drive it in. Seems like he said the warranty would only discount about $25 off a new one, so maybe i'll just buy one elsewhere and forget about the Nissan warranty.
Last edited by nlspace
on Fri Sep 20, 2019 2:34 am, edited 3 times in total.