AC Charging issue - but I don't think it's the dreaded CCU

QLeo

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Goth Leo our SE LR has developed an odd issue which we're trying to narrow down at the moment. The issue suggests it's the dreaded CCU problem, but there's a chance it's our cable.
We've not had any issues in over 2 years with the car. It's the generation that can do 3-phase charging, and we often use the 22kW pillar in the village. In February, we successfully used a 7kW pillar overnight across in the east in Dornoch.
A couple of weeks back, I was back in Dornoch, and again had reason to overnight. We plugged the car in to the same pillars as in February. Everything looked hunky-dory but when I checked on the app an hour or so later, the charge had stopped. We tried 3 other plugs in that cluster, but all exhibited the same issue.

On our return, knowing the CCU issue, I plugged in to the 22kW pillar. It charged without a problem for nearly 2 hours, which was all the time I had.

Yesterday we were in Inverness, and after a DC charge (which has always worked, by the way) we'd done a bit of ferrying around, so thought we'd park at a 7kW pillar while we went for a walk to add a few more percent. Two pillars failed to connect. The third connected, but stopped after perhaps 2%.

So it looks as though whatever the problem is is restricted to 7kW and/or single phase charging. I guess the next step is to try a different cable, as it is possible, I suppose (clutches straw) that it's our cable.

I can't tell from reading some of the many threads on the CCU issue whether it is restricted to single phase/7kW operation, given that 3-phase charging seems to work. It looks as though this may be the case but I can't find an example of someone reporting this.

But I would appreciate any comments, on my logic or on my straw clutch.
 
Have you checked the settings for AC current and what does the info button report?

Watch from timestamp 9:30 in this video


Thanks for that. I haven't changed any of those settings but will check them.
A neighbour who has a 7kW charger has kindly offered a charge to help determine the fault. They also have spare cables, which could be handy. In the meantime, I'll check those settings.
 
I've been wondering if Goth Leo would get the CCU problem eventually. At least if it is that we now know the fix and you have a good dealer.
You follow all the permutations and variations of this issue - do you think this is showing all the signs? I'm confused by the fact that it seems happy with 3-phase power.
 
OK, the plot thickens, but everything now points to using the 3-phase cable on a single phase (7kW) charger.
Our neighbour's Zappi connected quickly and easily using the tethered cable. I left the car charging for 1.5 hours without any issues. It suggests, unless it's a really random problem, that it may not be the CCU, but could be our cable.
In further extreme neighbourliness, they've lent us a 7kW cable they don't need. We'll try this on Saturday when we know we'll be at a 7kW pillar for the day.
It would be interesting to understand exactly how a 3-phase cable works on a single-phase connection, and indeed, whether duff cables are a thing.
 
Good luck investigating. I must admit I hadn't heard of cars having single phase problems but still charging on three phase AC. Of course it is possible, I suppose. DC charging should be unaffected however as it bypasses most of the CCU.

Do a comprehensive set of checks with different equipment to prove that there is a problem with the car. Remember this fault - if it exists - tends to get worse relatively quickly, shortening the period the car will charge for.
 
Good luck investigating. I must admit I hadn't heard of cars having single phase problems but still charging on three phase AC. Of course it is possible, I suppose. DC charging should be unaffected however as it bypasses most of the CCU.

Do a comprehensive set of checks with different equipment to prove that there is a problem with the car. Remember this fault - if it exists - tends to get worse relatively quickly, shortening the period the car will charge for.
That's helpful, thanks. Good that you've not heard of cars having single phase issues but OK on 3 phase, as that points to the cable too. I've been wondering if I should give the garage a pre-confirmed-problem call, but I'll hope for the best for the mo.
 
That's helpful, thanks. Good that you've not heard of cars having single phase issues but OK on 3 phase, as that points to the cable too. I've been wondering if I should give the garage a pre-confirmed-problem call, but I'll hope for the best for the mo.
When you go to the garage they need to be able to quickly reproduce the problem and not put it down to user error. For that, you need to be able to demonstrate it happening quickly and furnish them with your tests (preferably in writing) to show that you know what you are doing and they need to take it seriously. Too many garages will just throw in on charge for 10 minutes and declare the car working.
 
When you go to the garage they need to be able to quickly reproduce the problem and not put it down to user error. For that, you need to be able to demonstrate it happening quickly and furnish them with your tests (preferably in writing) to show that you know what you are doing and they need to take it seriously. Too many garages will just throw in on charge for 10 minutes and declare the car working.
Good advice, thanks.
 
Do you know what power you were receiving from the 22kW EVSE? I wonder if it is possible that the car charger can cope with just 2 phases if the EVSE does not trip on an unbalanced load. That would mean reduced power to the car compared to the normal 3 phase level.
 
Do you know what power you were receiving from the 22kW EVSE? I wonder if it is possible that the car charger can cope with just 2 phases if the EVSE does not trip on an unbalanced load. That would mean reduced power to the car compared to the normal 3 phase level.
That's a smart observation. But it was the usual ~11kW on 3-phase. I think I need to do as many chargers on AC as possible over the next little while to get some better data
 

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