Granny charger works only for a bit and then stops

[djr]

Hi all,

My granny charger seems to be working 'on and off'. Works for a bit, the stops, then I reset, works for a bit more, ... and so on.

As we are now in Winter and I don't do that much driving (only local) in comparison to Summer, so I've been putting 30-40 miles on the battery with the granny charger, which has been fine until now. I had the 3 year service completed last week, so I'm not sure if that has caused the problem.

When I plug the charger in it starts off OK and puts about 5 miles on, but then charging stops. There are 3 lights on the charger: 1) Power, 2) Charging and 3) Fault. When I start off the Power and Charging lights are permanently illuminated and charging is OK for a bit. Then the Power and Charging lights start flashing and the charging process stops. The Fault light doesn't come on at all.

The badge on this car has never lit up when charging. I did mention it during the recent service, but the message didn't travel through from receptionist to workshop. Both rapid and granny charging have been perfectly fine until now. I haven't tried rapid charging yet, but will do so in the next week.

Any ideas? The electric socket that I plug into is perfectly fine. It’s in the garage and I’m not using an extension lead.

 

[NIghtmare]

I'd suggest one of two things.
1. Borrow another granny charger to take it out of the equation
2. Take it back to the dealer. Plug it in there, using their charger as well, see if it persists.

 

[djr]

Thanks for the advice.
point 1 is tricky as I don't know anybody else with an MG ZS EV. I will definitely be doing point 2 in a week or so and trying out a rapid charge to see if that works.
Just thought somebody may have experienced similar behaviour or know what the flashing lights mean.

 

[Jomarkh]

Have you tried the granny EVSE at someone else's house as it could be an earthing issue.

 

[djr]

Have you tried the granny EVSE at someone else's house as it could be an earthing issue.

No, I doubt it will make a difference. House wiring is 3 years old and not raised any issues. Charged perfectly OK for about 40 miles 2 weeks ago.
Must be the car or charger. Probably something to do with the service. Some kind of software upgrade perhaps?

 

[Tim Green]

Which model or year is your car?
If the charging light is flashing it could be not connecting properly. I suggest you go back to the dealer and get them to check the plug and socket on car/granny charger.
But worth trying another granny first....

 

[Grriff]

If the charging lights are flashing, this may mean that the car is not ready to accept any more charge. I found on my MG4 that this was due to a scheduled charge set up on the car.
Have you checked that no schedule has been set up?
That the target SoC hasn't been reached?

I know that both of these are unlikely, since you have charged successfully before, but we are dealing with MG software. This seems to work on the basis of quantum mechanics: you know that faults exist but don't know what they might be until they happen.

 

[ShirLow]

Thanks for the advice.
point 1 is tricky as I don't know anybody else with an MG ZS EV. I will definitely be doing point 2 in a week or so and trying out a rapid charge to see if that works.
Just thought somebody may have experienced similar behaviour or know what the flashing lights mean.

Wouldn’t necessarily have to be from a other MG EV, just a granny charger from another electric car. Most are type 2 now aren’t they?

 

[Devoniageoff]

I had a similar problem and it turned out to be the house mains current was peaking beyond the normal voltage range (235 - 253v). EV chargers don't like that, so the chap from UKPowerNetworks told me! They can put a 'tap' on the line to keep it within the limit apparently. Hope this helps.

 

[djr]

If the charging lights are flashing, this may mean that the car is not ready to accept any more charge. I found on my MG4 that this was due to a scheduled charge set up on the car.
Have you checked that no schedule has been set up?
That the target SoC hasn't been reached?

I know that both of these are unlikely, since you have charged successfully before, but we are dealing with MG software. This seems to work on the basis of quantum mechanics: you know that faults exist but don't know what they might be until they happen.

I haven't set up a charging schedule (wouldn't know how to). Charging was fine until after the service. I've booked the car back in for the dealer to check over, but not until after Christmas.

I had a similar problem and it turned out to be the house mains current was peaking beyond the normal voltage range (235 - 253v). EV chargers don't like that, so the chap from UKPowerNetworks told me! They can put a 'tap' on the line to keep it within the limit apparently. Hope this helps.

Thanks, this sounds plausible although granny charging was fine for the first 3 months, using the same garage socket.
It charges fine for about 45 mins to an hour then I hear the handshake/synchronization noise and charging stops. If I flick the socket wall switch, unlock and relock charging starts again successfully for another 45 mins to an hour, ...and so on.
I've booked it back in to garage, but I'll mention this as it may be the issue.

 

[Jto]

You may find holding the plug in to the car then locking the and then let go of the plug after the hand shake may work as the cable can be pulling down on the plug and can lose contact. Had this on my car as the scocket is so high up.

 

[Mickky]

Have you by any chance fitted or have range extenders to your house WiFi system the things that plug into the mains and send the signal via the wiring as these have caused this sort of thing to happen in the past

 

[gazza487]

Have you by any chance fitted or have range extenders to your house WiFi system the things that plug into the mains and send the signal via the wiring as these have caused this sort of thing to happen in the past

I am one of the ones that had this with my 4 but apparently prevalent on earlier gen 1 Zs and 5s. Removed them and the problem went away and it’s a free thing to check if you do have them in your home.

 

[stewie1953]

Hi all,

My granny charger seems to be working 'on and off'. Works for a bit, the stops, then I reset, works for a bit more, ... and so on.

As we are now in Winter and I don't do that much driving (only local) in comparison to Summer, so I've been putting 30-40 miles on the battery with the granny charger, which has been fine until now. I had the 3 year service completed last week, so I'm not sure if that has caused the problem.

When I plug the charger in it starts off OK and puts about 5 miles on, but then charging stops. There are 3 lights on the charger: 1) Power, 2) Charging and 3) Fault. When I start off the Power and Charging lights are permanently illuminated and charging is OK for a bit. Then the Power and Charging lights start flashing and the charging process stops. The Fault light doesn't come on at all.

The badge on this car has never lit up when charging. I did mention it during the recent service, but the message didn't travel through from receptionist to workshop. Both rapid and granny charging have been perfectly fine until now. I haven't tried rapid charging yet, but will do so in the next week.

Any ideas? The electric socket that I plug into is perfectly fine. It’s in the garage and I’m not using an extension lead.

Hi,
We had exactly the same problem with our MG4 which we bought in March this year. Tried 2 different granny cables in several places and it always failed after 5-10 minutes, except of course at the dealership (!) who thought we were making it up. We thought it might be the car itself and the charging software, however, after about a month it stopped failing and has behaved as it should ever since. No reason, no explanation. If your MG4 is newish, it may just settle down. I realise this is not a solution per se but it may sort itself out because unless you can make it do it at the dealership where they can identify an actual fault in the granny charger.........!