Onboard charger capacitors failed

[SageBrush]

^^ Well done !

If you feel up to it, a tutorial how to swap the OBC would be a wonderful gift to the community since failed OBC stories are relatively common.

[wxmatt]

I figured I would update everyone on the progress…

Last week I got the new onboard charger installed and it is charging the car, but unfortunately it is leaking coolant. I have spent the last few days trying to make sure that it wasn’t just “user error“ on my installation and I have finally come to the conclusion that I think the charger is the cause. I can’t say that I am shocked, because when I got the “new“ used unit out of the box, the bleeder valve was bent about 30° and there were a couple of little dents on both the input and output coolant pipes. I took some pictures immediately so I had timestamped pictures, just in case. I went ahead and installed it anyway, because it’s not like there are a ton of used 2011/2012 chargers running around.

The leak is not gushing, but more like a trickle, and it’s not continuous . Basically, it’s just enough to make me question whether or not I’ve fixed it, or blead things correctly... but after five days now, I’ve reached the ultimate conclusion that it is an issue with the part. During that time frame, it’s probably leaked about a quart of the blue Nissan coolant… Which isn’t cheap.

I’m left at an odd crossroads: the part came with a warranty (in theory) of 6 months... but that warranty is invalid if I open the part up. Yet, I’m half tempted to take the electronic guts from this “new” charger and marry them to the cooling/mechanical guts of the original one from my LEAF.

[nlspace]

The problem with salvage yard parts: They have no way to test it before sending.

The problem with this salvage yard: they obviously didn't take proper care to pull or ship the parts to avoid damage.

How likely is it that they will have another salvage laef available to pull parts (another OBC) to replace it? How likely is it that they will be careful not to bang and bend up the coolant line?

Your plan to swap the electronics avoids anymore risk of getting damaged goods. You know it works plus you have already done half the job by pulling the electronics boards out of your original unit, and you know that it wasn't a leaker.

[wxmatt]

Your plan to swap the electronics avoids anymore risk of getting damaged goods. You know it works plus you have already done half the job by pulling the electronics boards out of your original unit, and you know that it wasn't a leaker.

Update: my Friday night plan to Frankenstein a charger has hit a smelly snag.




Looks like we had a failure in progress as we already had at least one explosion. I immediately noticed the discoloring and the smell when I opened it up and I’m frankly shocked that it was still charging the car in the state it was in. Before proceeding, I did get the OK from the salvage yard person that opening it would not void the warranty. Looks like this will be going back. The exploded part did not fail on my original charger, so in theory I could replace it, but I don’t know how confident I feel in that.

Sidenote… The more I look, the more difference I see between this charger with a model number 296A0-3NA0A, and my original 3NA5A. It makes me believe that there is reasonable enough value in buying the final revision 3NA8A part that is around $1400-$1600 dollars new from an online dealership.



3NA0A on top 3NA5A on bottom




3NA0A on top 3NA5A on bottom




3NA0A on top 3NA5A on bottom

I am sure that there are more differences, but at this point I’m probably not going to take this apart any more in the hopes of sending it back. I always ask God to make it obvious what my next step should be… He made this one VERY obvious!

[wxmatt]

I woke up this morning more positive than last night. I decided that if they tell me to keep the 2x broken OBC, that I’ll try to fix it. Considering it’s expensive to ship back a 2x broken part that they are unlikely or unable to fix, I feel like the odds are relatively good.

That means I’m on the hunt to find the right capacitor.

I did find the specs on that blown capacitor: 450v, 2.2uf Okaya: https://datasheet.octopart.com/AFC450V ... 87076.pdf

I know capacitors have different compositions for different activities, so as a novice, I put low confidence in this being the right solution, but I did find this that might work?? https://www.newark.com/panasonic/ecw-f ... dp/83X9334

[nlspace]

That one is close, but the lead spacing is too short, try this one

https://www.newark.com/panasonic/ecw-fe ... ecwfe2j225

it has a higher voltage rating with the same capacitance and correct spacing. If you can't find one i can pull one off of my board to send you.

The difference between the two versions. Your original has 2 empty fenced doghouse areas, these are populated by the AC EMI filter inductors on the salvage unit. Yours are likely external to the enclosure in the biege colored plastic box where the AC from the EVVSE comes in. That is the same style as my unit.

The potted transformers look different but do the same function, so no problem there.

[nlspace]

Maybe it's just a coincidence, but i'm leary that your EVVSE may be faulty. You have had 2 failures in the same functional section of the OBC, namely the PFC boost stage immediately after the AC rectification.

Do you still have the OEM level 1 version?

When you pull the board there are some diode voltage checks that you can do to make sure the waffle plate is not damaged.

[edit]
My impression is that the Juecebox started back in 2013 as an "open source" kickstarter project on the diy forum,
https://www.diyelectriccar.com/threads/ ... ign.59210/

but quickly went away from that when real money got involved. i doubt and would be surprised if anyone could ever obtain an open source schematic to diy build their own. i'm not impressed by someone using free open support to design and develop a product and then not making it freely available although touted as such.

The original "bad-boy" charrger design was seriously flawed, as would be all bad-boy concepts. So my personal opinion of them is very low, i would not use or recommend anyone to use it. i have never taken one apart to actually see how it is implemented, so i am ignorant in this respect.

[wxmatt]

I’m still awaiting word from the seller so I haven’t proceeded any farther yet buying capacitors or further dismantling the OBC.

The difference between the two versions. Your original has 2 empty fenced doghouse areas, these are populated by the AC EMI filter inductors on the salvage unit. Yours are likely external to the enclosure in the biege colored plastic box where the AC from the EVVSE comes in. That is the same style as my unit.

When the time comes, do I need to swap out the beige colored boxes between the two units as well?

I can easily open up my EVSE. I will take some pictures and send those. I intend to check the continuity along the cord because I believe that there is a short in it. I don’t know if the wrong wire shorting would cause this problem, but while I have access to both ends I intend to check that out.

[nlspace]

Pictures would be great; i'll take a look inside the beige unit if it can be opened to see what's in there.

[wxmatt]

After talking with the seller, and much debate, I’m going to send the used charger back. I am leaning toward buying a new one (at twice the cost unfortunately). While it’s possible that I am only a few minor repairs from fixed with the used unit, it’s also possible I go down a winding road that leads to even more issues. To this point, my wife has been extremely understanding, considering the car has essentially been out of rotation for 2 full months.

But... before I throw down the $1500 that a new on board charger would cost, I’m going to do more testing in the EVSE.

Do you still have the OEM level 1 version?

Yes. It’s still in great shape as the L2 has been the workhorse.

Maybe it's just a coincidence, but i'm leary that your EVVSE may be faulty. You have had 2 failures in the same functional section of the OBC, namely the PFC boost stage immediately after the AC rectification.

This is my concern too. I still believe that there may be a short in my cord and I plan to test continuity from both sides (as best I can) to check it out. I feel fairly confident that I know where the short is located, because it is where the garage would have sat on it prior to my purchase of a 3D printed pass through block. I’ve watched some videos about cord repair and plan on using “lineman’s splice(s),” staggered repairs, liquid electrical tape, and an adhesive lined heat shrink. I feel above-average confidence that I can execute the repair, but if not, I’ll replace the cord as long as the internals of the EVSE look decent.

The original "bad-boy" charrger design was seriously flawed, as would be all bad-boy concepts. So my personal opinion of them is very low, i would not use or recommend anyone to use it. i have never taken one apart to actually see how it is implemented, so i am ignorant in this respect.

So, I don’t know if I have the “bad boy” tor do I fully understand what that means, but here is what I do have:



I didn’t see anything obvious on first sight... nor smell anything particularly strong.





I did see these two pieces of plastic, but upon further review, I think they likely chipped off when the unit was originally assembled and the bolt in the last picture was installed.

Again, I cannot say thank you enough for all of your help, and I hope this thread proves useful for others in the future. I’m still holding out a slim hope that I can find another used OBC, but my EVSE is going to need to be vetted first.