Nissan Dealer Warns Customers: Using GE's WattStation Charger Can Damage Your LEAF

By · July 13, 2012

GE Wattstation

General Electric's WattStation Level 2 Charging Station has been blamed for breaking the onboard charging systems in multiple Nissan LEAFs.

A Bay Area Nissan dealership sent an urgent email yesterday evening warning customers to avoid using General Electric's WattStation to charge their LEAFs due to the possibility that the Level 2 home charge station could do damage to the car's onboard charger. The message from Hanlee Hiltop Nissan of San Pablo, Calif., stated that Nissan has identified multiple documented cases of cars losing their ability to charge after being connected to the WattStation. A representative of Hanlee Hilltop Nissan confirmed to that Nissan North America's regional operations manager sent an email to dealers yesterday alerting them to the problem.

A quick search of the MyNissanLeaf Forum reveals that reports of the issue may date back at least as far as April of this year, and that local dealerships have been forced to replace the onboard chargers in several vehicles across multiple states. Here's an excerpt of one of those accounts:

We've had our Leaf since May 19th but only driven it about 350 miles so far... charged it with our GE Wattstation maybe 6 or 7 times. Plugged it in to charge last Thursday, the charger came on, the charging lights on the car started blinking and then everything went off. Tried multiple times. Took it to a nearby Nissan dealer to plug into their charger. Nothing. Tried the trickle charger at home. Nothing. The Nissan Dealer we got it from came to our house Friday to run diagnostics which said the on-board charger was bad and he told us they knew of problems with the GE chargers causing this.


Though the precise nature of the flaw isn't clear, the problem seems to affect a diode in the LEAF's onboard charging system. In at least one case, General Electric offered to replace a LEAF owner's “defective” WattStation, but that owner was instructed by his local dealership not to use the replacement or Nissan would not repair his car under warranty if the problem occurred again.

Nissan and GE are reportedly working together to isolate and fix the issue, which so far seems to only affect the LEAF and not other plug-in vehicles. will continue to monitor this story and provide updates as they become available.

UPDATE: GE Energy's Sean Gannon has given us a little more information via the comment thread. Sean confirmed that the problem is limited to the LEAF and he says that so far it has affected 11 LEAF owners in total. He also points out that the WattStation is "designed and tested to the SAE J1772 and appropriate UL standards and these tests have been validated by an independent third party."


· · 5 years ago

Should I worry about charging my Volt with this charge?

I had a check engine light come on and my volt dealer told me that this indicated that my charger was not supplying enough power.

· · 5 years ago

Does this warning apply to the commercial GE Wattstations as well? Stone Brewing Co. in Escondido has one for free charges. I keep thinking one of these days I'm going to go up for lunch/dinner and charge while I'm there, but maybe not now.

· Doug Kornreich (not verified) · 5 years ago

I have had a GE Watt Station at home and it has worked flawlessly with my Nissan LEAF since December 31, 2011. The Watt Station complies with all of the J1772 standards -- the Nissan LEAF does not. The problems I have read about are blown diodes in the Nissan LEAF. This diode is supposed to be the signalling mechanism between the car and the EVSE pursuant to J1772. However the LEAF and Nissan's Aerovironment chargers to not comply with the standard -- they just ignore the diode. Accordingly, if the LEAF has a blown diode, the Aerovironment chargers will not notice, but the WattStation does and prevents the charge from occurring pursuant to the standard. Why the diodes are failing is not clear, but most likely it would be related to the car being exposed to a power surge that would blow the diode. The WattStation acts properly in refusing to charge once the diode is not functional. For the Nissan Dealers to say that the WattStations are the cause of the problem is misguided.

· David Becker (not verified) · 5 years ago


You explanation doesn't quite hold water because the article (and the forum member's quote) indicates that the LEAF would not charge on ANY charger. Not even the ones at the dealership (which would be a Nissan Aerovironment unit) or the LEAF standard trickle charger. If your theory is correct, those SHOULD work and just the Watt Station would not. But none of them do. However I agree that it's premature to point the finger solely at the GE Watt Station. They need to complete their investigation first.

· · 5 years ago


The message from the Nissan dealer warned against using any GE chargers. Though most of the incidents mentioned in the MyNissanLEAF Forums specify that a home charger was involved, it's probably best to avoid public WattStations until further notice.

· Sean Gannon from GE (not verified) · 5 years ago

Hi, this is Sean Gannon from GE Energy. As the article notes, GE has been actively working with Nissan to help determine the source of this issue, which has been raised by 11 Nissan Leaf owners. The GE WattStation has not encountered a similar issue with other brands of electric vehicles. Also, since its successful launch in 2011, WattStation has performed as designed, thousands of units have been shipped, and it has received positive reviews from EV drivers. It's also designed and tested to the SAE J1772 and appropriate UL standards and these tests have been validated by an independent third party. And there have been no design changes to WattStation since its 2011 launch.

· · 5 years ago

Thanks for the info, Sean! We appreciate any additional word you can give us as you guys work to resolve the problem.

· · 5 years ago

@Sean Gannon,
Thanks both for responding to this issue as well as for jumping into the EV market. I've corresponded with various avenues into GE customer service over the past few years, asking GE to get involved with EVs since, they seem like America's large company that will gain the most benefit from electrification of our roadways both at the consumer end and at the industrial (power generation) end.
It seems you are listening.
I of course, am partial to your wind energy programs but it is all good.
I hope you are successful in finding a good solution to the Nissan Leaf/GE Wattstation issue that works well for both companies and your customers.

· sub3marathonman (not verified) · 5 years ago

The GE Wattstation is not the only EVSE that this has been reported with. On Thinwing reports the very same problem while using a Chargepoint charger. The interesting part of that story is, "I had leaf plugged into evse ,not charging but waiting for timer,I had to cut power at the breaker to do other elec work.Evse reset ok but car does not respond with ohm load on pilot"

So while it is still possible that the Wattstation could be the cause of the problem, when other EVSEs exhibit the same behavior, it also shows that the problem is not specifically due to using the Wattstation. And since other EVSEs don't test the diode before charging, it is possible that other LEAFs have a failed diode without knowing.

· Randy (not verified) · 5 years ago

I've been up to the GE charger at Stone and used it with no problem...I wish now I would have taken a video (and hope to get back there to take one). The unit makes a very very loud buzzing noise when charging. At the time, I didn't think too much about it, but I want to go back up there and grab a video to forward to GE. It's difficult to have a conversation next to the charging station because of the humming/buzzing noise...More to come after I get a video....

· · 5 years ago

So what level 2 charger is recommended or is it better to use 110 volts ?

· Liz McCaughey (not verified) · 5 years ago

Thanks for this info and thanks to Sean Gannon for the extra insight. We are currently using this charger for our Leaf. We haven't had any problems up till recently.

We have experience some charging issues with not getting a full charge two or three days in a row last week (charging to 86 miles vs at least 96). But it's been charging okay after the third day. I was going to bring it in to have the battery checked... just in case... we have driven over 3,000 and we have had it since end of March.

My question is, how can I determine if it is the on-board charger going bad? Bring it to Nissan?

I'm hopeful that GE and Nissan will have an answer soon.
We are located outside of the Philly area in PA.

· · 5 years ago

I'm thinking tin whiskers. :-) Actually this is very strange. You would have thought with such a large sample size of LEAFs and EVSEs that this would have come to light awhile ago. I wonder if Nissan have changed their charger design.

· John K (not verified) · 5 years ago

Our has been trouble-free since last November, driving 60+ miles a day, charging every evening. Makes a big solenoid clunk when it fires up. It does hum, but very quietly.

· · 5 years ago

I hope this problem gets worked out quickly -- but can't help offering the following observation: The complexities and potential headaches involved with EV batteries, charging them, EV chargers, having an EV charger at home and/or EV with charging issues, and the fairly significant amount of knowledge needed to engage in an intelligent and informed exchange about problems such as this one using, what, for 99% of Americans, is jargon like "diodes", "level 2 charger", "SAE J1772 and appropriate UL standards," etc. is a big reason that EVs aren't going to be going mainstream any time soon -- as much as I wish they were.

· · 5 years ago

There are going to be issues like this, but they will be corrected (pretty quickly IMHO) and we'll move on. I have a BMW ActiveE and we have charging issues also. Schneider EVSE's won't charge the car at all. When you plug in, it won't even begin to charge. Coulomb public and home EVSE's register 'hard faults' frequently and the car shuts off in the middle of charging. Clipper Creek units have a similar reaction as the Coulomb ones do. However Blink, GE, SPX, AeroVironment & Leviton EVSE's all work without any incident with the ActiveE. Unfortunately, most of the public chargers in the AE filed trial areas are Coulomb (ChargePoint Network) so public charging has been challenging. BMW is working with each of the companies to figure out why the car has a problem with their specific equipment and correct it. At least it isn't causing a problem with the car like what is happening with the LEAF when using GE equipment. The worst thing that happens to us is the charging session is disrupted.

Christof: I don't see these charging issues as any impediment for mass adoption. They are minor and will be corrected quickly. Issues like this were bound to happen to any new technology. As far as EV's becoming mainstream "any time soon", that depends on how you look at mainstream. What do you consider mainstream? 5% of new car sales? 50%? I think it's going to be a slow evolution as opposed to a revolution. Personally, I'm just watching annual sales and as long as we continue to sell more plug in cars every year than we did the previous year, then we are on the right track to "mainstream".

· Anonymous (not verified) · 5 years ago

It's time to bring out the Frankenplug!

· Bill Howland (not verified) · 5 years ago

This is just more proof that the J1772 standard is dopey, and, far from being a "standard", EVSE's that meet the 'standard' and cars that meet the 'standard' don't work with each other.
I have a Schneider EVSE that meets J1772, and a Tesla Roadster that meets J1772, but they don't work together. Schneider was indignant when I pointed this out. I was left to redesign the Schneider unit myself to get it to charge the car. Now, in this blog we see a GE Wattstation permanently damaging a Nissan Leaf so that it can't use ANY charger. Again I say: What a Dopey Standard!

· · 5 years ago

"It's time to bring out the Frankenplug!"

Actually, anon, that probably wouldn't have changed anything here. The J1772 Combo (aka: "Frankenplug") has the exact same pinout on the Level 2 AC side of the plug. The difference with "Frankenplug" is the addition of the Level 3 DC pins grafted onto the other side of it, which only work when that sort of charging is occurring. There's something going on with particular brands of EVSEs those J1772 plugs are attached to and, perhaps, the Leaf's internal charger.

"So what level 2 charger is recommended or is it better to use 110 volts ?"

From what we're reading here, gorr, the problem seems to be isolated to a few (out of many available) brands of EVSEs when interfacing with the Leaf. Other brands of cars might have issues with other brands of EVSEs, as Tom is noting with his personal experience on his BMW.

Yes, this sort of thing is bound to happen in the early days of EV deployment and it appears, fortunately, that all companies involved are talking with each other to work out specific interaction problems.

When charging via 110V on a Leaf, the household cord gets plugged into Nissan's portable EVSE (comes standard with the car, typically carried around in the trunk in a nylon bag) . . .

. . . and that's what interfaces with the J1772 connector.

· Ken Clifton (not verified) · 5 years ago

Situation normal with the Web stirring up a bunch of mass hysteria and FUD (fear uncertainty and doubt)...

Common sense here please: Folks installing charging stations should be including a hard-wired high grade surge suppressor when the units are put in place. Reality check: With a charging station and car combination you are directly connecting over $30,000 worth of electrical equipment to the grid. How many folks have surge protection on their computers and TVs?

I have used a GE Wattstation to charge my Nissan Leaf every day (sometimes three times a day) for the last six months. In fact, that is the only charger that has been used with the car, except for its first charge at the Nissan dealership.

As others have mentioned in the comments here, there have been plenty of other diode failures on other chargers, but the common thread seems to be electrical interruptions, breakers being opened, etc... A few months back on the Nissan Leaf forums folks commented back to me about my surge suppressor recommendations that a surge protector is not going to save you in a direct lightining strike. Well folks, we are not talking about direct strikes here, the idea is to protect against surges...

If you have an EVSE, you really should have surge protection as close to the charger as possible – it is just simple common sense.

One other commenter here mentioned the state of charge percent and the Wattstation. The state of charge is controlled by the Nissan Leaf, not the EVSE. The EVSE/charger just connects the car to the power source – it only connects or disconnects when the Leaf says to.

Disclaimer: I don't work for GE and don't own GE stock. I do live in a small town with a GE plant that makes circuit breaker panels that is likely being closed next year according to the local paper.

Ken Clifton

· Bill Howland (not verified) · 5 years ago

@Ken Clifton

Well Sir you are of course, welcome to your opinion, but surge protectors dont seem to be either a positive or negative influence in this case.
Why do people say GE Wattstations hum loudly?
Why do Aerovironment units not cause problems with the Leaf?
Why did I encounter an incompatibility with my own cars and charging dock if they both conform to an ISO9000 standard? (SAE J1772, amoungst others).

My opinion is that the National Electrical Code, promulgated by the National Fire Protection Association, is itself a problem. For instance, all the years in the 60's and 70's when houses were buring down due to improperly installed aluminum wiring there was not even a mention that aluminum wiring needed any special care. The manufacturers of aluminum romex took it off the market quietly. This is simply another instance of collusion between manufacturers and regulatory boards. As a matter of fact, Aluminum romex wiring HAD to be improperly installed to be profitable for the electrical contractor. The added labor to put it in correctly more than negated the cost savings over copper in every case. In today's homes, aluminum is only used for very large wiring.

Why do we even need a charging dock with a really expensive plug? Why not just a ground fault interrupter such as you use for a hot tub? I believe the answer is the manufacturers of these charging docs saw $$$ because these things have unbelieveable markups, and got them written into the current NEC. Their big mistake in my opinion was writing a really dopey J1772 standard which is not failsafe (causes damage to leaf's), and nuisance trips in other cases (such as my experience).
Europeans have chosen their own 3-phase standard, incompatible with J1772, so now cars have to be country specific, and there's probably going to be all kinds of more 3-phase european to 1-phase j1772 converter box crap useless equipment and vice-versa for what should be a no brainer.

· Jim McL (not verified) · 5 years ago

Dear Mr Sean Gannon

I was at the Watt Station Launch in Mebane NC last year, and the Watt Station worked fine. But at a repeat event later that year it refused to charge my Think City EV. The staff brought me into the factory to try another Watt Station in the assembly area, which also refused to charge my car. Repeated attempts to discuss the problem over the next weeks were refused. The Think City EV works fine with every other brand of EVSE out there, I have personally used over 6 brands and the internet groups report success with all but the early Hubbel Pep Stations that have not been upgraded.

It is well known that there were two updates to SAE J1772 in 2010, and a few manufacturers ignored the second update. Think has worked with a number of EVSE manufacturers to iron out these problems. Unfortunately Patrick Bouchard is no longer with Think, he was spearheading this effort.

Two days ago I was at Stratus Solar in Chapel Hill NC where their new GE Watt Station refused to charge not only my Think, but also a Leaf, a Volt, and a Tesla Roadster.

I would be happy to assist GE in debugging their Watt Station design, Billy Futch in Mebane has my contact info. I am an electrical engineer in the automotive field (heavy trucking) and I have access to the SAE J standards.

Jim McLaughlin

· · 5 years ago

@Liz McCaughey: "We have experience some charging issues with not getting a full charge two or three days in a row last week (charging to 86 miles vs at least 96)."

The guess-o-meter (GOM) is not a reliable indication of your state of charge. What did the charge gauge indicate? 12 bars? 11 bars?

The GOM considers previous trips' efficiency in predicting remaining range. For example, if I drive around town, below 40mph, for a week straight, it will happily tell me that I can get 110 miles on a full charge. If then on Saturday I drive for half an hour on the highway, my overall efficiency went down. For the next few days, the car will report 80-90 miles/charge until that history of Saturday's trip fades to a distant memory. IMHO, the Leaf's "efficiency memory" is way too short, which contributes to the GOM's mood swings.

· · 5 years ago

@Bill Howland

A couple of observations / experiences about your points:
1) Why do people say GE Wattstations hum loudly?

We have two charging stations, a Wattstation and a Siemens 8EM1111. The contactors in both units hum rather loudly when engaged (charging). I believe it is a side effect of the relay coil magnet. The Siemens unit was provided through Duke Energy and is a very expensive charging station, probably five times the cost of the Wattstation.

2) Why do Aerovironment units not cause problems with the Leaf?

The AeroVironment units don't make use of the J1772 pilot signal line which is part of the SAE standard. Since the AeroVironment unit ignores the pilot signal, a car with a blown diode in its internal circuitry will still charge on an AeroVironment unit. It will not charge on any charger that utilizes the SAE standard J1772 pilot signal line (such as a Siemens or Wattstation).

3) Why did I encounter an incompatibility with my own cars and charging dock if they both conform to an ISO9000 standard? (SAE J1772, amoungst others).

I don;t think the SAE J1772 standard is being followed adequately. The best analogy is what happened about 10 years ago with the Sun JAVA standard and Microsoft's deviations from it. That ended in a court settlement, but we have no such mechanism to enforce the SAE J1772 standard (to my knowledge).

RE. Just using a 240 volt plug instead of a charging station. Since you are fortunate to have a Tesla, I am sure you have seen the new models that simply use a plug (or plugs).

I am sure there are others more qualified to answer your points than myself. I am a college professor. My experience comes from having two Nissan Leafs in the family.

On another forum the question was raised as to whether the Wattstation has a TVS protection diode to protect against surges on the J1772 pilot line. I looked for a schematic of the Wattstation but could not find one available. I did look at several photos of the Wattstation board which is a shared board for all GE charging stations, but the photos were not good enough. Just keep in mind that if there is an issue, the same circuit board is used in almost all of the GE units up through the high-end Durastations.

Ken Clifton

· Neal Roche (not verified) · 5 years ago

If you want to test an EVSE to see if it's safe and complies to SAE J1772, Gridtest Systems provides an automated test tool for the purpose. It runs more than 20 tests and gives a pass/fail report on the EVSE.

It is not priced for consumers, but many manufacturers and independent test labs have started to use the EVE-100 Test tool.

Neal Roche

· Bill Howland (not verified) · 5 years ago

@Ken Clifton

Point taken, except that the Tesla solution is non-standard, incidentally I've complained to Tesla that they now have a 3rd outlet again incompatible with anyone else. I had to purchase a $750 plus 8 3/4% tax 'converter plug', to work with my schneider j1772 charger, and then again, it didn't without a redesign, getting no assistance from them. Tesla was friendlier : "We hope you work it out Bill! Of course, if you don't we always have our proprietary chargers to sell you". I have used the roadster with several GE durastations, and they seem to work properly after they are properly configured.

Heaven forbid anyone ever comes out with a standard plug for cars that works. I would guess that we're married to this dopey J1772 thing, as the last thing I want is more incompatible plug systems. I'm just glad we didn't let the big experts devise new standards for TV plugs, Toaster plugs, Heater plugs, Range plugs, and Clothes Dryer plugs. Then obviously, nothing in the house would work. It is rather Silly Season when a charging dock which is a glorified light switch (its sole USEFUL function it to turn the juice on or off, unmodified) can't work right the first time out of the box, and now is damaging brand new cars.

· SMS (not verified) · 5 years ago

Hi -

Is the problem occuring with all model years of the Leaf? I just purchased my leaf and yes, put a wattstation in because it had the capability of being used outdoors, which many other did not -- and of course I only had to pay $750 for the Wattstation.

I wonder when Nissan or GE will put out some type of blurb about this. I really do count on the wattstation charging my Leaf.

· Bill Howland (not verified) · 5 years ago

@Ken Clifton

I dont understand the comment about the pilot in the Aerovironment. I tried charging my Roadster at a Nissan Aerovironment outdoor dealership with the Tesla set at 70 amps. It reset to 30 amps just like it was supposed to.

The charger also recognized when I stopped the charging from the car, proving 2 way communication existed. How could the Tesla have known about the 30 amps? BTW its not a default setting..... It also recognizes 8 amps from my volt charger. Thats apparently the only thing about this J1772 standard they got right. Incidentally, I see that the Durastation uses only #18 AWG pilot, and uses the safety ground for the other lead. Better hope all their connections are good...

· Bill Howland (not verified) · 5 years ago

Continuing from last post, can someone who owns a Wattstation tell me if the cord that goes to the car has 2 small wires in it, or just 1 like the Durastation does? This is in addition to the 3 #10 AWG power and ground.

Seeing as some people use Wattstations successfully with the Leaf, and some burn out a diode in the Leaf, if there is only one pilot lead in the cord as there is in the Durastation, I wonder if the people who are blowing out their Leaf Diodes have faulty green ground connections at their houses....If I knew someone personally having a problem with this I would have already investigated it, so that's why I'm asking. Thanks in advance.

· Gary Hanson (not verified) · 5 years ago

I am one of the 11 Nissan Leaf owners using a GE WattStation with a failed Leaf OBC unit. Initially the local Nissan dealership repaired the car under warranty, and warned me not to plug the car again into the WattStation until such time as Nissan and GE figure out what's amiss. We still don't know what the problem is, however, in the interim I was in direct contact with Nissan USA Customer Service (Mr. Paul Smith) who informs me that he had entered a "Statement for the Record" in my Nissan case file, that any dealership has access to, to the effect that any future OBC unit failure incident to my connecting the car to a GE WattStation would continue to be covered under warranty.

· · 2 weeks ago

Aw hell. Last comment here is five years old, and I seem to now be experiencing this with our 2011 Leaf. There are two GE WattStations at my wife's work, and my wife tells me that she's heard charging complaints from all the Leaf owners who use those stations, while others (Volt, Bolt, Tesla) have having no trouble.

In my case, our Leaf is now rejecting my two Clipper Creek units at home, and this has cost me much time and money already - as well as time, money and effort on Clipper Creek's part to help me chase this down.

Is there ANY further info on this? Man.

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