MG4 Not fully charging

andrewhs

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I have had an MG 4 trophy for two years zappi charger and octopus electricity supply . recently it will not fully charge ie adding approx 5 khw then stopping . Octopus and Zappi cannot find any faults , I have tried charging the car away from home and it works fine

Has anyone experienced anything similar ? or any thoughts on a fix
 
I have had an MG 4 trophy for two years zappi charger and octopus electricity supply . recently it will not fully charge ie adding approx 5 khw then stopping . Octopus and Zappi cannot find any faults , I have tried charging the car away from home and it works fine

Has anyone experienced anything similar ? or any thoughts on a fix
Hi, is that using IOG and is it the same when you select 'fast' charge on the Zappi?
 
I suggest you do so, to rule in/out your Zappi as being the problem. (Charging away from home on a DC rapid charger doesn't rule out your car as being the problem, as a DC charge bypasses most of the CCU that is used for AC charging).

PS - where in South Scotland are you? If you're anywhere near me you're welcome to use my home charge point as a test.
 
I have had an MG 4 trophy for two years zappi charger and octopus electricity supply . recently it will not fully charge ie adding approx 5 khw then stopping . Octopus and Zappi cannot find any faults , I have tried charging the car away from home and it works fine

Has anyone experienced anything similar ? or any thoughts on a fix
Have you tried using the granny charger?
 
If you haven't done so already double check the settings in the Zappi app also switch the Zappi off at the main fuse board for a couple of minutes before reconnecting so it reboots and installs any pending software updates.

There is a helpful Zappi forum myenergi
 
Best approach is to check for longer periods:

1. Will it take >50% charge increase on another AC charger?

2. Will it take >50% charge increase on granny charger?

3. Will it take >50% charge increase on Rapid DC charger?

If (1) and (2) fail and (3) works, you probably have a CCU failure (which happened to me) or other fault in the charging system. If it works on other AC chargers then it is probably your Zappi at fault.

The CCU fault develops over a few weeks, it starts as an occasional failure to charge fully on AC, then it happens more and more often until it won't even charge for 10 minutes without stopping.
 
Best approach is to check for longer periods:

1. Will it take >50% charge increase on another AC charger?

2. Will it take >50% charge increase on granny charger?

3. Will it take >50% charge increase on Rapid DC charger?

If (1) and (2) fail and (3) works, you probably have a CCU failure (which happened to me) or other fault in the charging system. If it works on other AC chargers then it is probably your Zappi at fault.

The CCU fault develops over a few weeks, it starts as an occasional failure to charge fully on AC, then it happens more and more often until it won't even charge for 10 minutes without stopping.
i tried it today on a 7kw pay charger and it kept stopping and starting , then tried it on a tesla dc unit and it worked fine , guess it is an issue with the car?
 
i tried it today on a 7kw pay charger and it kept stopping and starting , then tried it on a tesla dc unit and it worked fine , guess it is an issue with the car?
Yes, if you get the same results on several AC chargers and DC is fine, most likely you have the CCU failure problem (or a similarly related one).

Important thing is to tell the garage the exact things you have done to test this out, I suggest writing it down and leaving in the car for the technician to read. This will ensure they take you seriously and don't fob you off as "user error".

They will need to do their own tests to diagnose and decide what the fix is and then need to order parts. Don't be too surprised if they suggest software fixes are tried first, but make sure THEY test your car after any software updates to verify the fix properly, not send you home just to find it still doesn't work.
 
I have had an MG 4 trophy for two years zappi charger and octopus electricity supply . recently it will not fully charge ie adding approx 5 khw then stopping . Octopus and Zappi cannot find any faults , I have tried charging the car away from home and it works fine

Has anyone experienced anything similar ? or any thoughts on a fix
Yes, I have a similar setup, with 3 phase 22kW Zappi supplied by octopus. Had been able to charge at 11kWh for 2yrs until mid July when the car suddenly would only accept at 7kWh. Have checked out the Zappi with Octopus, no fault. Has there been a software update on the car that has interfered with the AC input regulation.
 
Yes, I have a similar setup, with 3 phase 22kW Zappi supplied by octopus. Had been able to charge at 11kWh for 2yrs until mid July when the car suddenly would only accept at 7kWh. Have checked out the Zappi with Octopus, no fault. Has there been a software update on the car that has interfered with the AC input regulation.
To get a software update, it would have to be done at your dealer, so it wouldn't have happened automatically - there are no OTA updates.

It is true that only early cars support 11kW hardware (phase 1 production), so yes, MG could have decided to limit this for everyone by a software change.
 
At the end of the charging cable in the plug there is a resistor which allows the car to recognise how much current it can draw. If ??? this has failed it could possibly default to a lower setting . It is likely that any Zappi checks overlooked this . There are Youtube videos on how to put a Multimeter across the relevant terminals but would require knowing what values you are typically looking for, to either confirm or dispel the possibility.
 
Have you tried using the granny charger?
Check your incoming electric supply, any more than 231v incoming will shut down your charger, I had this problem when I first got my car, even 240 v incoming is too much as chargers only allow for a 10% differential, I had to get Scottish power to lower it at their sub station, they purposely run it at higher voltages, as it stops complaints from the users at the end of the line
 
Check your incoming electric supply, any more than 231v incoming will shut down your charger, I had this problem when I first got my car, even 240 v incoming is too much as chargers only allow for a 10% differential, I had to get Scottish power to lower it at their sub station, they purposely run it at higher voltages, as it stops complaints from the users at the end of the line
This is bad information. Most of the country runs at 240V a little over, or a little under. No issues charging will be seen at 240V. 230 +10% is 253V. We never moved to 230V, we just agreed to the standard as most areas are set at 240V as they have been for decades.
 
A high voltage can be the issue, but as per above it is not 231V given that the grid specification allows 253V maximum.

Anecdote time - I was doing inspection work at a factory several years ago, making sure that our control cabinets had been installed and connected correctly in an equipment building. When it came to power-on tests all was going OK until we switched on the next cabinet and the incoming UPS supply tripped. I checked everything at our cabinet but the UPS supplier was still blaming us, so I asked him what time it was. After looking puzzled I suggested he checked the incoming AC supply to the UPS (which was a single phase supply tapped from a local 3-phase transformer in the factory) ... it was gone 4.30pm and most factories in the area were shutting for the day; this caused a reduced load on the grid and so the grid voltage creeped up, which meant the single phase tap voltage was at 257V - the UPS was set to trip the unit at 256V.

Score 1 for the controls engineer who used to do power station controls. 😎
 
Oh dear, I think mine is starting to develop the dreaded CCU failure. Last week I had a few instances of the charge just stopping after a short period and today the same has happened again (5 times so far). Mine is a Phase 2 SE SR though.

I'm pretty sure it's not the home charger but I will try it on a different AC charger round the corner. A couple of strange things. A couple of times when I've plugged in I've seen the charging port lights go yellow/orange briefly which I've never seen before. Also this has only started happening since I did my very first rapid DC charge but I guess that could be coincidence.

Guess I'm going to be trying to find a dealer tomorrow (the place I bought it from has closed). :(
 
At the end of the charging cable in the plug there is a resistor which allows the car to recognise how much current it can draw. If ??? this has failed it could possibly default to a lower setting . It is likely that any Zappi checks overlooked this . There are Youtube videos on how to put a Multimeter across the relevant terminals but would require knowing what values you are typically looking for, to either confirm or dispel the possibility.
This is a new angle I hadn't thought of. Just to confirm, are you suggesting that there is a resistor located within the plug that connects to the car, not the plug from the Zappi? ...and in the plug itself, not the car socket?
 

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