Issue with AC charging/New CCU fitted (Phase One SE LR)

DelBoy said:

All these cases seem to point at a batch issue, hopefully it'll be a slam dunk for my car when it goes to be examined. Are the replacement CCU units the same as the original ones (3 phase), and, has anyone actually use the 3 phase charging?

Click to expand...

Not sure if I’ve actually tried 3 phase since it was replaced, V2L definitely works though. I’ll try a 3 phase charger next time im near one.

tsedge said:

Yes, there's all sorts, I'll just try another make next time I charge. Thanks.

Click to expand...

I find these very easy to use:
Charge Point Map | Find an EV Charger Near You | Osprey

tsedge said:

Is this a one-off test or have you tried it like this for a while Steve?

I have tried a granny at 2.5kW and I get the same result (quickly stops) but not a very low charge rate - I could try that and see what happens.

Click to expand...

I’ve now tried it 5 times, on one occasion the charge stopped within seconds but the other times it charged continuously for several hours without fault, until either I stopped the charge myself or the scheduled 7kW charge came on, which then quickly faulted out again.

Steve T said:

Mine is going in for inspection in a week or so, but one interesting thing I found is that if I use the Zappi on eco mode, which charges at 1.5kW, it doesn’t cut out. But as soon as I switch to 7kW it stops very quickly. In the chart from the snip attached, I’m charging for a number of hours at 1.5 kW until the scheduled fast charge comes on at 0030, then the charge stops soon after.

Click to expand...

I tried the same, but the charge stopped after less than a minute, so no joy there, garage tomorrow, hopefully some news then

Yes these are the same symptoms I had, mine reliably stops quickly now so I've abandoned AC charging.

FiferMG4 said:

I charged the car this morning at an Osprey rapid DC charger and it was displaying the percentage as normal. Do you have any of those chargers nearby you that you could check with?

Click to expand...

It was the chargers, not the car, tried a BP Pulse this morning and it can read it. False alarm.

tsedge said:

It was the chargers, not the car, tried a BP Pulse this morning and it can read it. False alarm.
View attachment 22720

Click to expand...

Interestingly, that display looks exactly like the one on the Osprey. Anyway, I’m glad the charger is able to read the car’s SOC.

Hi folks!!
Has anyone actually had a fix yet in regards to the charging faults?
My MG4 SE/LR has been with the dealer (due to not charging at home or pod point etc) since mid December.
It's had all the updates but to no avail.
The latest is that I have a problem with the heating (cabin) system but to confound the issue MG have moved to a new reporting system over the Xmas period & mine wasn't "migrated over" & they can't fix the heater until MG say yes. I've shown them evidence from several forums that it's very probably the CCU but they won't consider it until the fault they have is fixed as they think "all things are linked".
Love the car but hate the treatment...

Birdy said:

Hi folks!!
Has anyone actually had a fix yet in regards to the charging faults?
My MG4 SE/LR has been with the dealer (due to not charging at home or pod point etc) since mid December.
It's had all the updates but to no avail.
The latest is that I have a problem with the heating (cabin) system but to confound the issue MG have moved to a new reporting system over the Xmas period & mine wasn't "migrated over" & they can't fix the heater until MG say yes. I've shown them evidence from several forums that it's very probably the CCU but they won't consider it until the fault they have is fixed as they think "all things are linked".
Love the car but hate the treatment...

Click to expand...

Hi Birdy, I had the software update that is supposed to fix the AC charging issue over a month ago now, and it has been solid as a rock, it's charged every time on my zappi without any issues. Hopefully it continues.

I said a few weeks ago in a previous post that it seems there is a software issue (which I had) and a hardware issue. My experience with my dealer so far has been ver positive to be honest, if I've had an issue I've reported it and they've done what they can to rectify it for me.

@Alex Brumpton is your profile correct and you have an SE SR? If yes then your issue was different to this thread - this thread seems mainly to be Phase 1 LR cars with the 3-phase onboard charger; these are almost certainly a hardware issue (perhaps married with a software issue).

@siteguru it looks like two threads have been combined?

Yeah mine is an SR but I did still have unreliable AC charging before it was updated. My dealer definitely knew about the issue though and where very confident the update would work and it has so far. Maybe it's more serious on the LR cars? Guessing at this point.

Has one tried charging at 3.6kW to see what happens as this is the internal configuration of a 3ph OBC.

When connected to a 1ph supply it is supposed to "bond" two charger pathways together, I wonder if the mechanism controlling the bonding has failed, and it is limited to 3.6kW and when trying 7kW it's causing an internal protection to activate to prevent further damage.

Edit: updated due to mistake pointed out by siteguru

Ayoull said:

When connected to a 3ph supply it is supposed to "bond" two charger pathways together, I wonder if the mechanism controlling the bonding has failed, and it is limited to 3.6kW and when trying 7kW it's causing an internal protection to activate to prevent further damage.

Click to expand...

Is that supposed to say 1ph supply?

siteguru said:

Is that supposed to say 1ph supply?

Click to expand...

It is I was writing this while on the phone

Ayoull said:

When connected to a 1ph supply it is supposed to "bond" two charger pathways together, I wonder if the mechanism controlling the bonding has failed, and it is limited to 3.6kW and when trying 7kW it's causing an internal protection to activate to prevent further damage.

Click to expand...

Mine won't charge from the granny charger either, I think some others have reported the same. It would be interesting to know the cause of the problem, maybe we'll find out.

Ok, my trophy has been into the garage to fix the charge once and stop. Confirmed by the garage, then some updates done, well a lot really. These are the modules updated (I did have an update to fix the DC charging issue on the EVCC previously): BMS, BCM, CCU, EVCC, IMCU. Tested Ok, further updates on FICM to R46 for the Bluetooth issue. Then updates to FDR and FUCM for the LKA.

Drove it back and put it on supermarket charger (thanks previous threat to test straight away), this time the car charged, stopped after a minute or so then started again, and over again, tried again on home charger and same issue. I'm guessing the tech looked at the charger and looked later still charging so fixed,.... but not fixed. Also the R46 was partially installed as the ACC changed by 1 mph each tap but the system stated still at R33 and the main screen still looked the same. Tech dude perplexed and tested further, stated that there had been more fault codes picked up by the garage test laptop in the time I have driven it about 40 miles so the consensus was it was buggered.

MG UK now contacted and awaiting a response from them. Garage good, I did have quite a few coffees there and everyone helpful so will see what we will see on what happens next.

Never seen so many abbreviations since my military days.

Ayoull said:

this is the internal configuration of a 3ph OBC

Click to expand...

That looks more like the configuration for a 3-phase motor controller, with the HV battery stuck on at the right hand end.

In the "single phase" diagram, you appear to be connecting to two phases, not to active (one phase) and neutral.

My guess is that the three-phase chargers are more like three separate ≈3.3 kW chargers, and you still need some switching to make use of a 7 kW single phase source.

DelBoy said:

so the consensus was it was buggered.

Click to expand...

Great to have a definitive diagnosis!

DelBoy said:

Never seen so many abbreviations since my military days.

Click to expand...

Yes, like an explosion in a Scrabble factory!

Coulomb said:

My guess is that the three-phase chargers are more like three separate ≈3.3 kW chargers, and you still need some switching to make use of a 7 kW single phase source.

Click to expand...

That's right the 3ph OBCs are actually 3 seperate 3.6kW chargers in one unit

It happens for me even with a granny, and for others even if you restrict the granny output, so it is irrelevant about 3 phase or the amount of power I think.

My own view is that an important component has failed, meaning that the CCU cannot properly detect the SoC and so it aborts the charge early.

I've heard via Miles that MG UK have 40 CCUs arriving on Valentine's day and 50 more soon after. Apparently the delay getting them has been because they come from a 3rd party supplier and they have had delays.

So the message is that there's a bunch coming and they are expediting delivery to the UK.

tsedge said:

It happens for me even with a granny, and for others even if you restrict the granny output, so it is irrelevant about 3 phase or the amount of power I think.

My own view is that an important component has failed, meaning that the CCU cannot properly detect the SoC and so it aborts the charge early.

I've heard via Miles that MG UK have 40 CCUs arriving on Valentine's day and 50 more soon after. Apparently the delay getting them has been because they come from a 3rd party supplier and they have had delays.

So the message is that there's a bunch coming and they are expediting delivery to the UK.

Click to expand...

Thank you for the update, tsedge. That sounds promising.

I’m guessing it’s because the battery hasn’t had a proper balance charge in three months, but I’m noticing I’m not getting 100% power now when accelerating. It goes to 98%. Also, after my last DC rapid charge, there was no regenerative braking effect until I got below 70% SOC, whereas normally it kicks in much higher at about 95%. Has anyone been experiencing similar discrepancies with their car?

evmick said:

My Dad's MG4 Trophy is having similar issues. Charges fine on DC including a trip to Scotland over Xmas, but not charging at home reliably, charging very slow and keeps dropping out. It will re-start fine if you have the time to keep podging the button in the MG app, but still charges very slowly.

Tried it on my charger here when they where visiting, and same issue.

His is booked in with Holdcroft MG Stoke on 5th Jan - will report back if they manage to fix it. They've quoted the software upgrade might fix it solution, but my hunch is a hardware issue and it had been working just fine up to then.

Click to expand...

Dad's MG4 LR Trophy in with Holdcroft MG Stoke today - pretty useless, claiming that it's my Dad's charger when we've tried it on 2 other 7kw chargers that are working fine with other cars (including my MG5). He has an MG4 courtesy car, so of course he should be able to prove that his charger is fine tonight when he gives that a charge, but customers shouldn't be intimidated into proving that they are telling the truth!