2011 - Dead Battery Charger

My Nissan Leaf Forum

Help Support My Nissan Leaf Forum:

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
The failure in my charger was pretty significant, so I'm not sure it's something that would happen slowly.

The car itself has insulation monitoring circuitry that will detect a short to chassis, so it's pretty unlikely that anything is damaged that badly if the car still drives and charges normally.

2011 Leaf? If so, you should be able to pull up the rear seats and see the charger. If the smell is really bad at that point, then it might be worth starting to plan for a replacement charger...

If there's no more smell there, I wouldn't worry too much and just keep using it.
 
I have another question, its been pointed out to me that the fast charger does not use the on board charger, my car wont charge on either fast or slow charge i am wondering if this is relevant to my diagnosis of crook on board charger?
 
Oh wow, sorry for the slow response! I've been out of the country and I didn't seem to get a notification that there was a new post!

The fast charger DOES use the onboard charger, but only for communications/signalling. The power connection is direct to the battery pack.

If the on-board charger is completely toast (not talking on the CAN, potentially no internal supplies active) then you wouldn't be able to charge from a DC fast-charger, so that fault description is consistent with your issue.
 
It's been working fine. Charged properly every night since, haven't smelled burning plastic again. So I haven't taken it into the shop. I'm probably going to trade it in on a 2018, so I'm hoping I can just ignore it until then.
 
I realise that this is an old topic, but the following may be of use to other intrepid charger repairers.

The Mitsubishi iMiEV has a Nichicon On Board Charger that appears to be similar in many respects to the one in at least early Leafs. For example, compare the OP's burned capacitor (it might actually be a relay, or two small capacitors near the relay) with the AC filter from an iMiEV charger:

qwikZ6J.jpg
sbLjAqU.jpg


I note that the components that frequently blow in the iMiEV chargers are the small blue (with green tinge) capacitors to the right of the potted "cage", and the square component near them is a relay (the pre-charge relay), not a capacitor. The Nissan charger has three pre-charge resistors (white blocks to the left of the cage), whereas the iMiEV charger has only two. One of the iMiEV pre-charge resistors is larger than the other, and contains an integral fuse. When the iMiEV small capacitors blow, they can cause quite a mess including that black muck, and could well be the cause of the OP's fault. I'm not convinced that the OP's large capacitor (which I think may be the PFC capacitor) has vented; it could all be "fall out" from whatever happened in the AC filter cage.

The cause of the iMiEV charger failures is not yet determined. One of the prevailing theories is that when the charge is suddenly interrupted for whatever reason (mains failure, in the iMiEV's case it could be the 20 A DC fuse on the charger's output going open circuit from metal fatigue), the energy in the charger's inductors has nowhere to go except into those tiny capacitors, which can't absorb that much energy, and consequently fail spectacularly.

Edit: there is a lot of useful information in the following myimiev.com topic, including some partial schematic traces (only at the edges so far, but includes the AC filter components), and even an intriguing X-ray photo of the Waffle Plate™ (a potted assembly with most of the high power semiconductors).

Troubleshooting and repair for On-board Charger (OBC), DC-DC Converter.
 
The location is definitely a film capacitor in the Leaf. Mine was melted and you could see the foil.

I severely doubt it's killing a film capacitor with over-voltage simply from inductor flyback, but unexpected open-circuit on the output could absolutely cause this kind of issue.
 
JonoNZ said:
The location is definitely a film capacitor in the Leaf. Mine was melted and you could see the foil.
Interesting, thanks. I thought maybe the small capacitors when they exploded might have caused the film capacitor (which I thought at that point was the relay) to be damaged and melt as a consequence, but on further investigation it looks like this is the wrong side for those small capacitors (C121 and C122 across POA and NOA, Positive and Negative Outputs before the final DC filter in the iMiev charger).
 
Just picked up a 2012 SL that will not charge with the Nissan L1 or at public L2 stations, but will charge at DC stations. I am getting these codes: b29c1 236c and p3173 00C0 so I got a charger from a wrecked 2012 to install this weekend ($550 shipped.) My question is about bleeding air from the charger coolant system. Does anyone have any steps or tricks for that procedure once I get everything hooked back up?

Thank you for any guidance you can provide!


Some background on the car:

Previous owner said it stopped charging on L2 and they took it to Nissan dealer - dealer quoted $2500 to replace the charger. The HV battery had been replaced in 2017 with what they claim was a lizard battery, but can't confirm that that it was actually a lizard or not. They didn't have the money to repair so they parked the car for 3 months with only 3miles of range remaining.... I bought it as-is and towed it home, but I stopped at a DC station with it on the trailer and filled it to 50% so I would be able to move it around at home. Even after the abuse of sitting near empty, the car still has all 12 bars and shows 53.07ah and 83% SOH in leafspy which I think is pretty good for a 2012 and a 3 year old battery with abuse.
 
I don't even really remember the bleeding process so I'm sure it was pretty straightforward. It's also an electric pump and relatively small lines, so I think the coolant speed is both constant and high, which helps.

I collected all the coolant that I drained quite carefully, which let me be pretty confident there were no huge bubbles in the system providing I could get it all back into the loop. I think I spilled about 1/2 a cup or so during the process, so I wasn't expecting perfection. I also think I went through the bleeding process relatively quickly and then just left the car in 'ready' mode for a couple of hours to clear any bubbles.

On the positive side, the worst case load into the cooling system for the on-board charger is 400-500W, which is pretty solidly nothing for cooling power electronics. Most of that is coming from a single huge module in the charger too, which helps a lot.

The 2011 service manual has the procedure listed in the 'HCO - High Voltage Cooling' section.

https://ownersmanuals2.com/nissan/leaf-2011-repair-manual-high-voltage-cooling-system-hco-43099

Page 9 has draining and refilling.
But the manual basically says:
There's a bleeder plug on the bottom side of the on-board charger, next to where the coolant inlet/outlet are. Remove that.
Completely fill the degas tank.
Remove the joint in the coolant hose at the 'traction inverter front', which is the hose closest the hood at the very front of the engine bay (motor bay? under-hood area?). Visually check for water flow and reconnect, which I'm guessing means 'does any leak out'.
Refill degas tank.
Close the bleeder plug on the charger and close the degas tank cap. I vaguely remember coolant trickling out a little at this point.
Start the car into 'ready' mode (foot on the brake, press power button, car should chime and come on with a green car icon with arrows under it on the dash, this is the 'ready to drive' mode which has the HV active) which turns on the pumps.
Watch the level in the degas tank and refill as it lowers.
Once the level has stopped falling, close the cap and turn the car off. Turning the car off with the cap open may cause coolant to surge out of the cap.

From there, it's basically make everything quiet, turn the car on and run the pumps for a minute, checking to see whether you hear gurgling from the back of the car. If so, there's still air and let it continue to bleed.

Hopefully that helps. Seems like you might have gotten a sweet deal for what is hopefully very little extra effort!

I've actually been discussing the possibility of repairing the ZE0 on-board chargers as they seem like a 'common' enough fault that, here in NZ at least, getting replacements out of wrecked vehicles is only just keeping up with demand. Still not anything to worry about, but definitely one of the more common faults. Maybe as many as 1% of cars having it happen in their lifespan, I'd hazard a guess?
 
@JonoNZ - fellow pixie wrangler here. When removing the OBC, did you follow the steps in the manual to the letter? Were there any steps that could be skipped? I ask because getting underneath to disconnect the HV cable seems hard to do without a lift. How did you do it?

My car has the same issues as some of the other comments (won't take a L2 charge and the pilot signal diode trick didn't work).

Is there any chance for warranty coverage or am I SOL?

My leaf is a 2012 model with 70k miles on the OD. Had battery replacement done under warranty in 2017, already down 3 bars.
 
I did not have the manual to go by, but I can give you an overview of the steps I took:

1.) Backed rear wheels up on ramps
2.) disconnect 12v battery
3.) Pulled the main HV battery service plug on the floor in the back seat
4.) removed upper and lower back seats and plastic coverings from trunk
5.) Loosened bolts holding the OBC in
6.) disconnected all plugs on OBC
7.) under the car pulled the plastic belly an off.
8.) clamped both coolant hoses with long flat locking vice grips
9.) undid clamps holding hoses to OBC
10.) let remaining coolant come out of OBC
11.) Re-install everything in reverse order with new OBC
12.) Hooked coolant hoses back up still clamped, then undid vice grip clamps
13.) topped off coolant in engine bay
14.) Started the car and let it run for about 3 hours to purge any air from coolant and topped off again.

All is good. Mine is a 2012 with 51k miles. Battery replaced in 2017 - still has 12 bars showing, 54.87ah and 86.12 SOH Still have my old OBC if someone is interested in it for repair or testing?
 
Hi defenderred,

Sorry to hear you're having issues. Just to double check, your 2012 is one of the ones with the charger under the rear seats? There are a few here in NZ that are the AZE0 chassis number type registered as 2012 which causes some confusion.

You shouldn't need to get under the vehicle to disconnect the electrical connections, that's all present in the cabin, under the seats.

You do need access to the underside of the front radiator to drain the coolant loop and then to the underside of the on-board charger to disconnect the coolant lines. There's also a bleed port there that you might want to use for re-assembly. I don't recall there being a whole lot of slack in those lines, but there might be enough to let you get the charger lifted enough to get at the clamps, I'm not sure.

Stripping the rear seats out is a really easy process, so I'd recommend doing that first. It'll make planning what you do next much simpler.

Hopefully that helps. Let me know how you get on or if you have any other questions!
 
Clamping the coolant lines is a good idea. I was originally going to use it as an opportunity to replace the coolant, but it looked pretty much perfect so didn't bother in the end.

These chargers aren't particularly repairable as the power module in them is completely custom (made by Nichicon) and pretty much impossible to acquire replacements for, economically speaking. It would be possible with an un-damaged module, but that would require coming across a charger that had failed in a different way, likely the extra-low voltage section, which would probably be an easier repair directly.
 
I believe that the Leaf has a very similar but not identical charrger to the Mitsubishi iMiEV. Their charrgers fail often enough that Mitsubishi USA has extended the warranty on them, and many owners have had faulty charrgers replaced for free. I don't expect Nissan to do likewise.

In the iMiEV charrgers, there are two common failures, both involving inexpensive parts. But the gotcha is that to remove the lower printed circuit board, you need to desolder dozens of pins. A desoldering station is required for that. Some repairs have been done without removing that board, however. No one has reported failure in the potted power electronics plate (dubbed the "waffle plate") so far, that I know of.

So repairs are presumably feasible for the Leaf version. The best resource for the iMiEV charrger is this topic:
http://myimiev.com/forum/viewtopic.php?f=23&t=4079

[ Edit: oops. Looks like I already posted about this last year. Sorry for the double post. ]
 
Potentially, but I think you're several extrapolations deep there.

In many of the cases I've seen with the Leaf there's a dead output electrolytic and some evidence that it may have been caused by or have caused a significant output voltage transient, which in turn may have stressed other components within the power module.

I'm hoping to have a chance to look into some potential repair/diagnosis work in more depth, so I'll check out that thread on the iMiEV charger.
 
Well, it looks like you're probably on the right track there. The configuration and rating of the charger is a bit different so there are some associated part swaps (DC link electrolytics, input filter components etc.), but it seems to be built on the same topology, power module and shares all the same magnetics.

Looking at it, I think there's a pretty good potential that at least some of the same design faults exist in both designs.

EVs Enhanced in Christchurch, New Zealand are working on being able to repair or provide repair instructions/replacement parts for faulty on-board chargers for the Leaf, so they may be able to provide a similar service for iMiEV chargers as well.
 
Hi Jono (and the rest of this thread)

I'm also based in NZ and a couple of years my G1 stopped charging. I replaced the OBC with a used one and it worked fine. I wrote the error codes on the old OBC and threw it into the back of the shed. They were:
B2820 - 028 VC63
B2840 - 016C VC74
P3173 - 00C1 EVC236

A friend's G1 Leaf is now refusing to L2 (we don't L1 in the land of 240V) charge with these codes:
B29C1 232E Charger EVSE VC-98
U1000 00C0 EV/HEV CAN Comm Circuit
P31B8 00C0 EV/HEV CAN Error EVC-287
P3173 00C0 EV/HEV On Board Charger Sys EVC-236

Looks similar but the CAN errors worry me. I don't recall if there were more errors than I wrote on mine & I don't recall the detail of each of the errors. Also the fact that on the day it stopped working they found, "an ant's nest" in the EVSE connectors!

Two questions:
1/ Do you think a replacement OBC would be the best way to start? (I do!)
2/ Jono, do you work with Walter & co @EVs enhanced or do you just know them? I'd love to be able to get these repaired & it looks like I might have 2 donors for the job :) I'd be happy to donate them to the cause of research if they're wanted.
 
Hi Niall,

How interesting, always good to see someone else who has had some success swapping bits around and keeping their Leaf on the road!

Your old OBC:
B2820 is a quick-charger malfunction signal or voltage detection issue.
B2840 is a output over-voltage or over current general malfunction or a few more specific things like extreme output ripple
P3173 is echoing that the OBC has an error.
I think the ants-nest was probably unrelated.

That's a pretty interesting set of DTCs for sure and could be related to quite a few scenarios.

Your friend's OBC:
B29C1 is an EVSE signal fault which could be either the EVSE itself or the OBC.
The CAN errors are common when the OBC loses power and stops communicating or something goes wrong internally which takes it off the bus (or something else takes out the CAN for a while if there are other CAN errors in other systems).
P3173 is just echoing the OBC error as above

I'd probably try clearing the errors and see what comes back. If the CAN error comes back, replacing the OBC is where I'd go. If it doesn't, I'd try with a different EVSE and see what happens.

I've known Walter for a little while now and we've been looking for a way to collaborate. So far we're in the early stages, but learning some promising things about the OBCs. There are definitely a range of faults and it's likely that only a subset are viable to repair, economically and practically speaking, so we're trying to identify which those would be at present. Any extra units would always prove to be helpful, as it's more evidence for which faults are common etc.! I'm sure if you gave EVs Enhanced a call they'd be interested in whatever help could be provided, and able to help you with sourcing a replacement etc.

Whereabouts in NZ are you? I'm based in Auckland, personally.
 
Back
Top