I have looked in the '13 manual and can as of yet not find the type of fuses that are required. I agree these fuses should be accessible without the removal of the battery pack. I would guess they would be bolt on 60A HRC (24KW/400V for the feeder but may be sub fed by independent fuses for HVAC). Because of the possibility of the high ampere inrush current with a bolted fault it is a good idea that they would be difficult to access but should be replaceable with proper troubleshooting by qualified personnel ( without the removal of the pack)...IMHO.QueenBee wrote:A local 2011 LEAF had the AC compressor short to ground which blew the fuse in the DC/DC junction box and the battery junction box. They aren't getting it repaired by the dealer as it'll cost as much/more as the car is worth. So looking through the service manual sounds like a fun enough project. What I'm curious about is if anyone has attempted to repair these two fuses? It's not dealership serviceable but it'd be a little disappointing if these really weren't replaceable by someone with a bit of electronics skill.
I have not, however here is a link to a picture of the fuses in the DC/DC junction box.QueenBee wrote: What I'm curious about is if anyone has attempted to repair these two fuses? I
Wow, I had not seen this site before!cliff wrote:I have not, however here is a link to a picture of the fuses in the DC/DC junction box.QueenBee wrote: What I'm curious about is if anyone has attempted to repair these two fuses? I
http://www.marklines.com/img/report/en/ ... _014_l.jpg
I see there is a 4th fuse in the picture in addition to the 3 that are clearly tied
to high voltage.
Thinking about this, a short to ground should not have done anything. One ofQueenBee wrote:A local 2011 LEAF had the AC compressor short to ground which blew the fuse in the DC/DC junction box and the battery junction box.
Ah good point, the tech specifically said ground but yeah he must have really meant the negative. A short to ground would have actually been easier to fix as it would have detected this happening and shut the car down, then it would just be the compressor being replaced.cliff wrote:Thinking about this, a short to ground should not have done anything. One ofQueenBee wrote:A local 2011 LEAF had the AC compressor short to ground which blew the fuse in the DC/DC junction box and the battery junction box.
the main safety features of the Leaf is that neither side of the battery is connected
to ground(somewhat like power in a hospital). So the positive must of shorted to
the negative, but only the positive had a fuse to protect the wire, so what
happened to the negative? With the fuse in the battery box going, this would
suggest to me that the negative could have taken more current than it should
before the fuse went. Is this a design error not having a fuse on the negative
side? But once the positive fuse went, then why did the other fuse go?
The 3 fuses in the DC/DC junction box are all 30 amp fuses, to the heater,
charger, and compressor. the 4th fuse is a 15 amp for the converter.
Ah, true, seems possible that both legs could fail to ground. I'll know more when I talk to our local LEAF tech when he's back tomorrow. More good news: He's optimistic that they he'll be able to get approval to install used parts and I made it clear that I would not expect any warranties of the parts and any additional diagnostic/rework time as a result of the use used parts/defective parts/etc. would be on me. He said the time to replace the compressor and DC/DC junction box is 8 hours and 4 hours to replace the junction box in the battery. So add $200 for a used compressor and the labor bill will be about what I was expecting it was going to cost just to have them replace the compressor!GerryAZ wrote:If the compressor circuit failed one leg to ground and then the other leg to ground, the other fuses could see short circuits and blow (depending upon where the grounds were in relation to the fuses and main contactor). The DC ground detection system would try to open the main contactor to isolate the battery as soon as it detected the first ground, but fuses would blow if the grounds became short circuits quickly. Have you checked the main contactor and insulation to ground of all high-voltage wiring? Good luck with your repairs.
I've been trying not to bug the tech on his days off so haven't started pestering him with questions. I believe I'll get a copy of the quote this evening when I get the title but this is what he said was wrong so I've been looking around based on that information.JeremyW wrote:Looks like you got it all settled before I wandered in, QueenBee. I would do the same thing, swap the dc/dc junction box and then teardown the dead one.
It's not clear to me, but I suspect the only the fuses in the dc/dc junction box are blown. In the 2011-2012 cars, the main pack fuse is in the orange disconnect that is in the backseat footwell. Does the car otherwise start and drive without AC?
The 2013+ cars have a different "HV junction" setup, and thus the 2013 service manual wouldn't be much help, Electric Eddy. At any rate, Nissan does module swaps and wouldn't have a normal tech replace fuses in the dc/dc. For example, we've seen the same with 2011-2012 chargers and diode issues: they always just replace the entire charger.
The car isn't driveable right now. It will be interesting to figure out exactly what is wrong with the battery junction box. Maybe it has fuses as well as the fuses in the service plug?The high voltage side of the A/C compressor shorted to ground and blew the fuse in both the junction box internal to the battery and the fuse inside the DC/DC converter.