LEAF Software Caused OBC To Fail, Not WattStation-fix coming

Hey, Sean Gannon from GE Energy's Global Media Relations and Public Affairs, just send me an email saying that Nissan and GE's investigation into WattStation and LEAF charging failures was complete, and asked me to do an update/put out a story on the results.

He said that the LEAF's on board charging software was at the root of the problem, and that a fix is coming...but you can still use the charger without warranty issue, but GE suggests to not use in brownout conditions or in intense storms, etc (I guess use common sense until Nissan patches the software).

If you want to check out the article I just put out, you can find it here:

http://insideevs.com/investigation-complete-nissan-software-issue-to-blame-for-ge-wattstation-damaging-leafs-fix-is-coming/" onclick="window.open(this.href);return false;

Jay

Is there or will there be a corresponding message from Nissan? With GE's announcement basically saying "It's not GE's fault" I'd hope to see something confirmatory from Nissan.

what was getting damaged? the EVSE or the onboard charger? and why was it only when connected to a GE EVSE? I'm totally confused.

palmermd said:

what was getting damaged? the EVSE or the onboard charger? and why was it only when connected to a GE EVSE? I'm totally confused.

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The LEAF's onboard charger was getting fried, so that it couldn't receive charges.

I'm guessing that while the WattStation charge conforms to acceptable UL/SAEJ1772 standards, the threshold was a little higher for tolerance in the GE EVSE over other platforms, and the LEAF's OBC/OBC software wasn't quite up to the task of dealing with that. /imo

I guess it makes sense that an under-voltage condition might overload the charger, and that the car should protect itself. But that doesn't explain why this issue particularly affects the GE/Leaf combination. Do other EVSE perhaps have low-volt cutoff of their own that has been protecting the LEAF? Or does the LEAF perhaps have a voltage tolerance that is less than whatever standard (if any?) that EVSEs must adhere to?

palmermd said:

what was getting damaged? the EVSE or the onboard charger? and why was it only when connected to a GE EVSE? I'm totally confused.

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The diode in the Nissan Leaf charger is being damaged, preventing it from passing a valid pilot signal back to the EVSE.

Why only the GE Wattstations? We don't know but I theorize that it has to do with the power supply they are using since other stations don't seem affected.

Unless a fix is ready, people are still in danger of damaging their car, and having to deal with a time consuming repair. Fixing the blame doesn't really change the situation much.

Statik said:

Hey, Sean Gannon from GE Energy's Global Media Relations and Public Affairs, just send me an email

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I'm mentally substituting "John Watson from Nissan Customer Service" in the above, and not getting a particularly satisfied feeling. Time will tell.

DarkStar said:

The diode in the Nissan Leaf charger is being damaged, preventing it from passing a valid pilot signal back to the EVSE.

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My understanding is that after the WattStation related failure, nothing will charge the battery. With the classic diode problem, non-compliant chargers such as the AV and the Panasonic L1 charger still work.

gbarry42 said:

My understanding is that after the WattStation related failure, nothing will charge the battery. With the classic diode problem, non-compliant chargers such as the AV and the Panasonic L1 charger still work.

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My understanding is that it depends on the failure mode of the diode. If it fails shorted, those EVSEs would still work. If it fails open, no EVSE will function.

Nubo said:

I guess it makes sense that an under-voltage condition might overload the charger, and that the car should protect itself. But that doesn't explain why this issue particularly affects the GE/Leaf combination. Do other EVSE perhaps have low-volt cutoff of their own that has been protecting the LEAF? Or does the LEAF perhaps have a voltage tolerance that is less than whatever standard (if any?) that EVSEs must adhere to?

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Exactly my question. The explanation is lacking a lot of important details... probably ones that GE doesn't want to disclose.

To be fair I think the communication was more oriented to letting people know they've found the problem and can thus implement a fix, than satisfying my somewhat idle curiosity.

If it's just a software patch then should come quick.

Nubo said:

If it's just a software patch then should come quick.

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Yes, but that would mean that anyone who has or might plan to use the GE Wattstation would have to go to the dealer to get a software update? Rather inconvenient, not something I would bother with. Of course, new Leafs would come with the updated software.

I don't see how a software fix can keep a diode from being damaged. :roll:

But, if there is a software fix, maybe it will fix the end timer issue with the SPX EVSE. :lol:

Stoaty said:

Nubo said:

If it's just a software patch then should come quick.

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Yes, but that would mean that anyone who has or might plan to use the GE Wattstation would have to go to the dealer to get a software update? Rather inconvenient, not something I would bother with. Of course, new Leafs would come with the updated software.

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Unless Nissan deny it, it appears they admit the defect is on their side. In which case I'd take my LEAF in even though I don't have a Wattstation. There's no proof evident that this can't happen with other existing (or future) EVSEs. And of course I might have occasion to use a Wattstation at some point.

Nissan apparently put out this statement:

"Nissan and GE have completed their investigation into the instances of
Nissan LEAFs experiencing on-board charging (OBC) issues when using
certain EV chargers. Nissan has traced the root cause of the issue to
the LEAFs OBC software that can allow damage to occur to its OBC
components while using certain chargers and in certain instances, such
as when a brief under voltage or blackout condition occurs. Nissan is
working to address this issue as quickly as possible, and in the
meantime is advising customers to avoid charging during times when
brownouts or momentary power dips may be likely, such as during
electrical storms or high power usage on the grid."

TomT said:

Nissan apparently put out this statement

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FWIW, I found that text on GE's website - so it appears that it's GE's statement.

http://www.ge-energy.com/leaf-wattstation-facts.jsp" onclick="window.open(this.href);return false;

GE is much more proactive about addressing these issues than Nissan... If Nissan reacted after 11 LEAFs lost a bar they'd have tested the affected LEAFs months ago.

pchilds said:

But, if there is a software fix, maybe it will fix the end timer issue with the SPX EVSE. :lol:

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There'd have to be an investigation, first :roll:

the schneider electric evse will drop out at 197v on the low end and 262v on the high end.this is a very wide range I dont know what can be done as these were done on a leaf many!!! times.the leaf and the schneider seem to talk just fine.

bryan38401 said:

the schneider electric evse will drop out at 197v on the low end and 262v on the high end.this is a very wide range I dont know what can be done as these were done on a leaf many!!! times.the leaf and the schneider seem to talk just fine.

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In keeping with this idea (also own a Schneider EVlink unit, no issues at all); what kind of voltage drop would one expect during a typical 'brown out'; you know when you see dim incandescent bulbs or flickering? When this happens at our house. sometimes during peak electrical usage times, sometimes during bad storms, our voltage drops low enough to trip the (old) A/C condenser unit and cuts out the cold air from our furnace --- furnace still runs because unaffected but we need to reset the breaker for the A/C unit to restore air conditioning --- this 'season' we've only seen this once and was while the car was plugged in but on its timer for charging later that night --- the indicator light on the unit remained green, and this brown out had no effect. It sounds like the 197v would be an extreme situation but not so sure how much the voltage would drop during a 'typical' brown out ... any thoughts?

bryan38401 said:

the schneider electric evse will drop out at 197v on the low end and 262v on the high end.this is a very wide range I dont know what can be done as these were done on a leaf many!!! times.the leaf and the schneider seem to talk just fine.

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I think what needs to be done is to measure the -12/+12 volt rail on the power supply while varying the voltage to the EVSE. I suspect this is the cause in the Wattstation but I'm not sure we'll ever know!