Main computer and HV wiring change

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DarthBane

Member
Joined
Apr 12, 2017
Messages
8
My 2015 Leaf is at the dealership for about 3 weeks now (parts on back order). It has been worked on for active 10 hours minimum, and the result is that they need to change all the high voltage wiring, and the main computer. Water infiltrated in the main computer, and it's cold where I live, so it froze there, causing damage to the computer. If I had to pay from pocket, this repair would cost between 4000-5000 Can$, not something I fancy paying later on. Fortunately, all this is under warranty, and the dealership has treated me very nicely.

What I'm after here, is an idea of how common this issue is. I've been told it is not supposed to happen, the main computer is supposed to be sealed and no water can get in there, normally... But it happened, and my dealership has seen this 3 or 4 times so far. So if they saw it 3-4 times in just 1 dealership, this is not a completely uncommon issue. My concern is that after they do the repair, these parts will be under warranty for 1 year. I am worried of this happening again in a couple of years, and I am starting to consider getting rid of the car before that warranty expires. But, anyone else had this done? I searched the forum but didn't find anything about it, maybe I searched wrong... I've been told that maybe Nissan Canada can tell me the numbers, but I thought I'd start here.

Please let me know if you had, of heard of this problem before, and it anybody had this occur twice.

Thanks a lot!
 
No water in the dash. The computer managing the HV circuit is in a box under the hood I've been told.
That being said, if I've been told wrong, no collisions, no cracks, and no water in the dash. The water infiltrated into the computer box only, which is a "sealed" box.
 
Lithium battery controller (LBC in Nissan's manual also called BMS for battery management system on this forums) is inside the sealed battery case under the car. As far as I know, all other control modules (computers) are inside the car either under the dash or in the console. There are some items under the hood that have controllers built in such as the inverter, DC-DC converter, onboard charger, and brake master cylinder (called intelligent brake controller in the manual).
 
Ok, LBC under the car, that must be the one. I apologize if I did not identify the computer exactly, it's just that the car is still at the dealership waiting for the parts, and they just told me that the main HV computer and all HV wiring need replacing because of the ice damage.

I just want to know if this is common or not, because it is a 4000-5000$ repair that I am not willing to do after the warranty is over. This will be a big factor for me to decide if I keep it or not.

So, anybody knows someone that had this issue? From the lack of positive answers on this, I assume it is still an uncommon problem, which is good news.
 
DarthBane said:
Ok, LBC under the car, that must be the one. I apologize if I did not identify the computer exactly, it's just that the car is still at the dealership waiting for the parts, and they just told me that the main HV computer and all HV wiring need replacing because of the ice damage.

I just want to know if this is common or not, because it is a 4000-5000$ repair that I am not willing to do after the warranty is over. This will be a big factor for me to decide if I keep it or not.

So, anybody knows someone that had this issue? From the lack of positive answers on this, I assume it is still an uncommon problem, which is good news.


The LBC is located inside the battery pack. The battery pack is sealed from water intrusion with a rubber gasket (2011/2012) or glued (2013+). If water got into the battery pack, it would be very bad, as it would short cells or busbars. Either short would result in cells overheating and over-discharging, which would quickly destroy them and possibly start a fire. A busbar short could be up to 400V, which would almost certainly start a fire.

I have never heard of water getting into the battery pack on a Leaf. You could wait to see if anyone else reports this, but I would seriously doubt it. That said, I would be shocked if the failure was a LBC due to water intrusion. If it were, I would demand that they explain how the battery case leaked water, and confirm that the leak was fixed.

I think it's far more likely that a different computer component was affected. If you want to confirm how common the failure was, you're going to have to understand exactly what failed and where the leak was.
 
I see, ok, I will report back when I get the car back. I know they took the battery out, but not sure why... and they are not replacing the battery. I think it was part of the troubleshooting process. Anyways, I'll keep quiet now until I know exactly what they had to do. Thanks for enlightening me!
 
DarthBane said:
No water in the dash. The computer managing the HV circuit is in a box under the hood I've been told.
That being said, if I've been told wrong, no collisions, no cracks, and no water in the dash. The water infiltrated into the computer box only, which is a "sealed" box.


Did they refer to it as the IPDM?
 
Ok, the part to be replaced is called PDM (Power Distribution Module). It sits on top of the motor, that is the 1st thing you see when you open the hood. But of course it is in a sealed box.

Hope this helps!
 
There was a recall for some years for PDM reprogramming, but it had nothing to do with water intrusion. I too have never heard of this. If 3 or 4 of them have failed there because of water intrusion, then either your locale has something extreme and bizarre going on weather-wise, or...the dealership is lying. What were the symptoms, and did anything water-related happen before they began?
 
Nothing water related happened, in case you mean if I crashed in a ditch full of water or such other incident.
The way it started is the yellow light (EV System warning light) turning on on the dashboard instead of the green arrows. When the yellow light turned on, I could not put the car in drive nor reverse, but only in park or neutral. So I got it towed to the dealership. They had a fairly quick look I think, and thought it was a simple switch or relay that froze and caused the light to turn on. They erased the code, and let me go. The car was working after erasing the code.
The next day I was at the office, started the car, all was good, but while driving the EV warning light turned on again. So I went straight home (didn't want to turn it off because I didn't know if it would restart or not). Parked it at home, turned it off, and turned it back on, and the yellow light was still on, and again could not engage drive nor reverse. Because of what the dealership had done, I decided to delete the code myself with LeafSpy. Then the car was good for roughly a week, and the EV light turned on again.
At that point I didn't want to just delete the code because then we would never find the cause of this problem, so got it towed again. That is when the dealership took a while to find the problem of water infiltration. The water infiltrated through the HV wiring, and this is why they want to change the wiring as well. They think the water came from condensation more than from a splash from the road or something like that.
That is pretty much the whole story!

PS: as far as weather goes, we had a real shitty winter: +5º C one day, the next day -20, so you can imagine what kind of ice rink we had on those days. But still, no water should go in there no matter what weather we have.
 
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