There is another thread where someone was in a situation where both their 12V & drive batteries were depleted, but the situation I came home to this morning was a little different. Ten days ago I parked the car in the garage with two bars of charge left on the gauge. Not wanting to charge it up & leave it sit for 10 days, but also not having time to babysit charging it up "a little", I left it disconnected figuring that I would just plug it in when I returned home.
When I got home this morning, the car was totally unresponsive. A voltmeter across the battery (under load) indicated ~2 volts. I probably should've disconnected from the car to get a better reading, but I figured dead was dead. I also figured that either the drive battery went totally flat trying to keep the 12V battery charged, or that for whatever reason the 12V battery must've discharged in less than five days before the car was able to get around to try & charge it.
Since I didn't have another car handy at the moment to try a jump, I called Nissan Roadside Assistance to request a visit from a booster battery. I explained that the car was in my garage & ready to connect up to the EVSE , and all I needed was to boost the 12V battery a bit so I could begin charging. They put me on hold, only to come back & tell me that they would need to tow the car to the dealer (!). They said they are not allowed to jump a LEAF. When I said that the procedure is right on page 6-10 of the owener's manual, they put me on hold again, for much longer. When they came back on the line, the Roadside rep told me she had a "Volt Technician" (lol) from a local Nissan dealer on the line. He also toed this ridiculous line that jumping the car was verboten & that the car needed to be towed to the dealership. When I asked what they would possibly do differently at the dealership than what I was asking for in my garage, he was at a loss to explain. He also didn't know that the owner's manual explains the jump procedure (which is really no different from any other car). He just kept saying, polly-want-a-cracker-like, that it needed to be towed in.
At that point, I decided to terminate the call & wait for my wife to get home. When she did, as soon as I connected the jumper cables, it was like the car woke from a deep sleep. I was able to turn it on & noticed that there was still one bar/12 miles available on the clock. I disconnected the jumper cables & the LEAF stayed on. Now my voltmeter was showing 13.1V across the battery; apparently now the car was OK with charging the 12V battery from the drive battery. I hooked up the EVSE & it has been happily charging for about three hours now. I had a look inside the cabin, but no map lights, etc. were left on that would caused the 12V battery to go flat.
I understand that the telematics are always drawing power, but I was very surprised that the 12V battery would totally discharge in the space of 10 days given that the drive battery was not yet fully discharged. If the car is not running, it seems like the priority should be to the 12V battery since you can't (easily) open locked doors, release the parking brake, or charge the drive battery without it.
I was also surprised at the FUD displayed by both Roadside Assistance & the "Volt Technician" WRT trying to jump start the car. I clearly stated that it was in my garage with the 240V EVSE nearby, so even if the drive battery was fully flat I still had a way to charge it. Had this happened in a parking lot or on the road with no way to charge the drive battery, that would be a different story. I understand that Roadside Assist is just a contractor, but it seems like Nissan is feeding the same nonsense to them as they are to their LEAF techs in the field.
I'll keep an eye on my 12V battery over the next few days, but I'm wondering if it's possible that there might some boundary-condition flaw in the LEAF's 12V charging rules?
When I got home this morning, the car was totally unresponsive. A voltmeter across the battery (under load) indicated ~2 volts. I probably should've disconnected from the car to get a better reading, but I figured dead was dead. I also figured that either the drive battery went totally flat trying to keep the 12V battery charged, or that for whatever reason the 12V battery must've discharged in less than five days before the car was able to get around to try & charge it.
Since I didn't have another car handy at the moment to try a jump, I called Nissan Roadside Assistance to request a visit from a booster battery. I explained that the car was in my garage & ready to connect up to the EVSE , and all I needed was to boost the 12V battery a bit so I could begin charging. They put me on hold, only to come back & tell me that they would need to tow the car to the dealer (!). They said they are not allowed to jump a LEAF. When I said that the procedure is right on page 6-10 of the owener's manual, they put me on hold again, for much longer. When they came back on the line, the Roadside rep told me she had a "Volt Technician" (lol) from a local Nissan dealer on the line. He also toed this ridiculous line that jumping the car was verboten & that the car needed to be towed to the dealership. When I asked what they would possibly do differently at the dealership than what I was asking for in my garage, he was at a loss to explain. He also didn't know that the owner's manual explains the jump procedure (which is really no different from any other car). He just kept saying, polly-want-a-cracker-like, that it needed to be towed in.
At that point, I decided to terminate the call & wait for my wife to get home. When she did, as soon as I connected the jumper cables, it was like the car woke from a deep sleep. I was able to turn it on & noticed that there was still one bar/12 miles available on the clock. I disconnected the jumper cables & the LEAF stayed on. Now my voltmeter was showing 13.1V across the battery; apparently now the car was OK with charging the 12V battery from the drive battery. I hooked up the EVSE & it has been happily charging for about three hours now. I had a look inside the cabin, but no map lights, etc. were left on that would caused the 12V battery to go flat.
I understand that the telematics are always drawing power, but I was very surprised that the 12V battery would totally discharge in the space of 10 days given that the drive battery was not yet fully discharged. If the car is not running, it seems like the priority should be to the 12V battery since you can't (easily) open locked doors, release the parking brake, or charge the drive battery without it.
I was also surprised at the FUD displayed by both Roadside Assistance & the "Volt Technician" WRT trying to jump start the car. I clearly stated that it was in my garage with the 240V EVSE nearby, so even if the drive battery was fully flat I still had a way to charge it. Had this happened in a parking lot or on the road with no way to charge the drive battery, that would be a different story. I understand that Roadside Assist is just a contractor, but it seems like Nissan is feeding the same nonsense to them as they are to their LEAF techs in the field.
I'll keep an eye on my 12V battery over the next few days, but I'm wondering if it's possible that there might some boundary-condition flaw in the LEAF's 12V charging rules?