Leaf will not charge. Displays "Ventilation Required" on EVSE

[MrDude]

So this one has me stumped.

2014 Nissan Leaf. Noticed it didnt charge when I left home.
Back at home, I plugged it in and my EVSE showed a ventilation required error.
Thinking my EVSE had an issue, I tried the Nissan supplied charger from the bag in the back. Plugged it in the wall, ready light came on, plugged it into the car, and it never lit up again. (its now broken)

ok. hmm. Still not thinking anything was wrong with the car itself, and that it was just my EVSE I tried the only ChargePoint in town. It also stopped and displayed a "ventilation required" error.

Ok. So I understand how the J1772 pilot communication works. Pilot is being pulled to ground hard.
I had to wait until today because it has been raining for days, but I hook my Fluke multimeter up between the pilot and ground.
One direction.. no reading. Nothing. Nothing at all. not even in the mega-ohm range. big old OL
Swap leads, and I get a 337 ohm reading. Not Kilo-ohm, 337ohm. Thats almost a dead short to ground.

Just in case, even though it is a new 2 month old battery, I have the 12v battery on the charger right now so its at the top.

So now I am grasping for ideas. I have not opened the charger lid yet and would rather not unless I have to.
This car has not been in any accident and the wiring for the ports looks undisturbed. I dont think there is an abrasion issue causing a wire short, but maybe one is common??

I need some ideas guys... and if it comes down to it, does anyone have a charger board for a 2014? It can be without chademo. (I dont have it, and no point converting to it since there are almost no local chargers)

 

[Lothsahn]

This video shows the cause of most charger failures. I'm assuming you've already seen it:
https://www.youtube.com/watch?v=5R4dGg8nIUs

Thankfully with the 2014 the charger stack is in the front of the car, so the repair is a lot easier than shown in this video and there's a lot less cabling involved.

 

[MrDude]

This video shows the cause of most charger failures. I'm assuming you've already seen it:
https://www.youtube.com/watch?v=5R4dGg8nIUs

Thankfully with the 2014 the charger stack is in the front of the car, so the repair is a lot easier than shown in this video and there's a lot less cabling involved.

yup. Its one of the few informational bits I found on it.
unfortunately I dont think the diode is the issue, from my check results... and diode D5 wouldn't be the same on it anyway as the 6.6kw charger in the stack is a different design.
If you have any videos about that one though, or any other checks, I would like to see them.

 

[LeftieBiker]

I don't think it's the 12 volt battery, for the simple reason that all of the error messages are for the same issue, rather than being random. I think that this "ventilation" message is real, but I've never heard of it. I'm sorry. I wouldn't try to charge it again until it gets diagnosed.

EDIT: this is all I could find. It appears to relate to lead-acid-powered EVs, so is an old programmed EVSE function - a throwback to an obsolete situation. Strange...

https://groups.google.com/forum/#!topic/openevse/84dGYmLOOaM

 

[WetEV]

Lefty is correct, the control pilot line is in status D, meaning the Leaf seems to think it has acquired lead acid batteries. :roll: :lol: Fits with the resistance reading you are getting as well.

https://en.wikipedia.org/wiki/SAE_J1772#Control_Pilot

 

[Lothsahn]

Lefty is correct, the control pilot line is in status D, meaning the Leaf seems to think it has acquired lead acid batteries. :roll: :lol: Fits with the resistance reading you are getting as well.

https://en.wikipedia.org/wiki/SAE_J1772#Control_Pilot

Yep, Leftie hit the nail on the head this time. Turns out he's right sometimes! (Just kidding Leftie, you're great).

As indicated, you are not measuring the resistance you should be. You either have a fried pilot resistor (in the charger) or a wiring problem, or both. You'll need to check wiring continuity of the pilot and ground lines, and then repair or replace the charger if there are no wiring faults.

Your EVSE is almost certainly undamaged and is behaving as it should in the specification.

Good luck!

 

[LeftieBiker]

Turns out he's right sometimes!

That was one of the two times a day that I'm usually right.

 

[MrDude]

2 years later follow up on this for anyone that stumbles across something similar.

What this means, is water is in the charger wires/connector, near where they go into the charge stack.

If you let everything dry out, clean and reseal everything, its fixed.

 

[ChusGS]

Hi, same problem here from yesterday.
This afternoon will try cleaning and drying wires and connector.
Have you pulled out the plastic shield above the radiators (to access back side of connector) or it isn't necessary?

 

[coulomb]

2 years later follow up on this for anyone that stumbles across something similar.

What this means, is water is in the charger wires/connector, near where they go into the charge stack.

I would have thought that in the OP's case at least, the problem had to be after the diode, since the extra continuity is only in one direction. The diode in the 2011 and 2012 models is inside the on-board charger, and I'd expect the same for the later models.

I wonder if, just to get things working temporarily at least, you could add a resistor in series with the control pilot wire (much like the diode fix, but with a resistor instead of a diode), so the EVSE doesn't see the need for ventilation. Something like 620 ohms (560 or 680 ohms might be easier to find) would take it from around 246 ohms combined resistance after the diode (ventilation required) to around 882 ohms (connected and ready for charging). The best value might have to be found by trial and error. I note that the resistance reading seen by a multimeter is inflated by the voltage drop across the diode; that drop is far more significant to the multimeter than to the control pilot signal. I'm surprised that you can get any reading at all from the resistance range; usually these operate at low enough voltages that diodes don't turn on. With some multimeters, on the diode range, it reports resistance in ohms up to a certain limit, so you can get an idea of the resistance behind the diode.

Of course, this crude fix would only work if the problem is just that control pilot resistor (R2 on the Wikipedia J1772 diagram) going low in value, and that nothing else is affected. This seems unlikely to me, though it might then lead to a more meaningful fault code. It seems a shame to cut up the control pilot wire just for diagnosis, but it saves the trouble of getting at the on-board charger.

Edit: A colleague tells me that "it's never the diode". So it seems that having the diode fail shorted, therefore being amenable to the external diode fix, is actually quite rare. This despite the tone of the above video, and many people's expectations.