Can't get a fast charge on ChaDeMo charger socket

[DaveinOlyWA]

I rashly decided to take my family on holiday in my 2012 Leaf, which I have only owned for a few months and never fast-charged before, even though we had to go 150 miles to get to our destination. I plotted a route and got to the first fast charger with 10 miles to spare. Plugged the ChaDeMo in and... nothing. The charger just shut off after about 20 seconds without charging. We made it to another charger and tried again. Same result: swiped the card, machine said Charging session starting... and then nothing. It just shut down after about 20 seconds with a message on the screen: Charging session ended. We had to leave the car with a dealer, but when we got back a week later they said they couldn't do anything because they didn't have a ChaDeMo charger, and the diagnostic machine needed them to plug it in at the same time as the diagnostic was connected. Since then I have contacted 3 local dealers and none of them has both the ChaDeMo charger and the diagnostic equipment. Has anyone else had this problem of not being able to fast charge their Leaf? And how did you get the problem fixed, if you did? Thanks.

You get any warning icons on the dash? If so, clearing the code might fix the problem. More common on AC than DC but I have seen it in my own car a few times.

[clivech]

Isolation errors are essentially internal short circuits, and they are the kind of errors that cause the system in which they appear to shut down. (I had a 2015 Zero SR that exhibited them.) If you could tell us when you bought the car, who sold it, etc, we may be able to determine if this was a known problem when the car was sold to you.

Hi LeftieBiker:
Sorry for the slow response, I've been away. Thanks for the suggestion. I bought the car in May 2022 from a none-too-salubrious looking "garage" in West London. The chap I bought it from had stopped communicating with me when the problems started piling up (the touch screen didn't work and I had to spend a lot of money and time cannibalising another unit sent from America to get it to work). He has now resumed contact after I posted a one-star review on Google!

[clivech]

I rashly decided to take my family on holiday in my 2012 Leaf, which I have only owned for a few months and never fast-charged before, even though we had to go 150 miles to get to our destination. I plotted a route and got to the first fast charger with 10 miles to spare. Plugged the ChaDeMo in and... nothing. The charger just shut off after about 20 seconds without charging. We made it to another charger and tried again. Same result: swiped the card, machine said Charging session starting... and then nothing. It just shut down after about 20 seconds with a message on the screen: Charging session ended. We had to leave the car with a dealer, but when we got back a week later they said they couldn't do anything because they didn't have a ChaDeMo charger, and the diagnostic machine needed them to plug it in at the same time as the diagnostic was connected. Since then I have contacted 3 local dealers and none of them has both the ChaDeMo charger and the diagnostic equipment. Has anyone else had this problem of not being able to fast charge their Leaf? And how did you get the problem fixed, if you did? Thanks.

You get any warning icons on the dash? If so, clearing the code might fix the problem. More common on AC than DC but I have seen it in my own car a few times.

None at all. Just the codes from LeafSpy.

[clivech]

Isolation errors are essentially internal short circuits, and they are the kind of errors that cause the system in which they appear to shut down.

Agreed, except that isolation failure could be leakage, not a hard short. For example, it could be due to road salt getting near the CHAdeMO high voltage wires or pins, causing a leakage to chassis when the salt absorbs moisture. If the leakage was after the quick charge contactors, this would not affect driving or AC charging, only quick charging.

Leakage is also the kind of phenomenon whereby the application of high voltage can slowly cause current to increase over many seconds, explaining the ~20 second delay before charging shuts down. If that's the case, cleaning the back of the CHAdeMO connector with alcohol might fix it. I would pull the high voltage disconnect before attempting this, or leave it to the techs to do that. Though it seems unlikely to me that the fault fixing procedure would include something so simple and practical.

[clivech]

Those errors actually look like communication errors between the car and charger, The isolation error is actually isolation signal error. I had similar charging failures with a couple DCQC units shortly before my 2011 met its untimely demise. I attributed it either to charger connector wear or charge port wear. There were times when I was able to charge after clearing error codes with Leaf Spy.

Hi Gerry:
Thanks for this. Looks like I should have a go at cleaning the pins in the CHAdeMO socket, maybe with a cotton bud and alcohol. They look clean enough, but that could be deceiving. The LeafSpy history shows the CHAdeMO charger has been used several hundred times successfully during the life of the car, so it's probably a somewhat recent issue. I'm in two mind about clearing the codes: the LeafSpy manual says don't do it until you know what caused the code, which I don't. But I do have a screenshot of it on my phone. Do you think clearing them now would be wise?

[clivech]

I didn't mean to imply hard shorts, but i guess I did anyway. Yes, signal leakage on the CANBUS seems likely. The isolation errors on the SR could actually be cleared, but would reappear in pretty short order, so to speak.

Sorry, Leftie, but what/where is the CANBUS?

[clivech]

Seems unlikely if the CHAdeMO charging is the only symptom, but isolation signal errors suggest CANbus errors, and CANbus errors suggest a weak and/or poorly charged auxiliary battery. Can we eliminate the auxiliary (12V) battery, perhaps by giving it a really good charge and trying again soon after?

I replaced the 12V battery just 6 weeks ago. LeafSpy shows it has good voltage.

[clivech]

Isolation errors are essentially internal short circuits, and they are the kind of errors that cause the system in which they appear to shut down.

Agreed, except that isolation failure could be leakage, not a hard short. For example, it could be due to road salt getting near the CHAdeMO high voltage wires or pins, causing a leakage to chassis when the salt absorbs moisture. If the leakage was after the quick charge contactors, this would not affect driving or AC charging, only quick charging.

Leakage is also the kind of phenomenon whereby the application of high voltage can slowly cause current to increase over many seconds, explaining the ~20 second delay before charging shuts down. If that's the case, cleaning the back of the CHAdeMO connector with alcohol might fix it. I would pull the high voltage disconnect before attempting this, or leave it to the techs to do that. Though it seems unlikely to me that the fault fixing procedure would include something so simple and practical.

Hi Coulomb:
Sorry, I replied but it only posted your original post. This sounds electrically plausible (although I know the discussion has moved on after this to signal problems), so how do I get to the back of the CHAdeMO connector to clean up the connections?

[cwerdna]

I didn't mean to imply hard shorts, but i guess I did anyway. Yes, signal leakage on the CANBUS seems likely. The isolation errors on the SR could actually be cleared, but would reappear in pretty short order, so to speak.

Sorry, Leftie, but what/where is the CANBUS?

https://en.wikipedia.org/wiki/CAN_bus#Automotive

CHAdeMO uses CAN for communications. viewtopic.php?t=4131 mentions that Leaf has at least 3 CAN buses.

[DaveinOlyWA]

Those errors actually look like communication errors between the car and charger, The isolation error is actually isolation signal error. I had similar charging failures with a couple DCQC units shortly before my 2011 met its untimely demise. I attributed it either to charger connector wear or charge port wear. There were times when I was able to charge after clearing error codes with Leaf Spy.

Hi Gerry:
Thanks for this. Looks like I should have a go at cleaning the pins in the CHAdeMO socket, maybe with a cotton bud and alcohol. They look clean enough, but that could be deceiving. The LeafSpy history shows the CHAdeMO charger has been used several hundred times successfully during the life of the car, so it's probably a somewhat recent issue. I'm in two mind about clearing the codes: the LeafSpy manual says don't do it until you know what caused the code, which I don't. But I do have a screenshot of it on my phone. Do you think clearing them now would be wise?

Definitely clear the codes. That is for the tech and as long as you have a record you are fine. Clearing these codes could fix your issue