Vehicle Control System Fault (limp home mode for a few seconds)

[MG4ismyfirstEV]

So, to add to the list of issues on my gorgeous orange MG4.

while on a test run to see if the oil leak issue in the car had been fixed I had the following happen on 4 or maybe 5 occasions.

An alert noise and visible would appear on the screen behind the steering wheel stating vehicle control system fault. At this time the engine power would drop considerably and the cars ability to brake reduced too. Like a limp home mode (zero kers braking available too).

Within seconds another message would appear on the screen, stating Speed Limit Cleared. With that message, all would return to normal.

So, dear MG4’ers, apart from the fact I am going to take it back to the dealers / get it recovered, has anyone else experienced this or knows of it? Is it an easy fix, unlike the oil leak lol.

Just want a car that works.

Thank you all for reading.

 

[the briggie]

Sometimes strange messages like this can relate to low 12v battery. Normally a longish drive clears them. Another MG4 feature perhaps

Alan

 

[MG4ismyfirstEV]

Sometimes strange messages like this can relate to low 12v battery. Normally a longish drive clears them. Another MG4 feature perhaps

Alan

12 v battery is currently showing 12.7 v.

 

[the briggie]

That rules that out. Sometimes dealers just disconnect and reconnect the 12v before getting down to serious diagnostics. Not recommending it just stating they do that as a reset option first.

Alan

 

[MG4ismyfirstEV]

If it can happen once. It can happen again. Losing power and brake efficiency is dangerous.

If it resets and doesn’t happen again. Then I might be convinced.

 

[MG4ismyfirstEV]

That rules that out. Sometimes dealers just disconnect and reconnect the 12v before getting down to serious diagnostics. Not recommending it just stating they do that as a reset option first.

Alan

Maybe. But it could freak out again for no reason too. Dangerous when power drops and braking efficiency takes a nose dive.

 

[the briggie]

Maybe. But it could freak out again for no reason too. Dangerous when power drops and braking efficiency takes a nose dive.

Agreed, hence not recommended. However my current confidence of certain dealerships service departments, going by this forum, is not high. With potential software errors I suspect the temptation would be to disconnect/reconnect and take a test drive and if all is clear regard it as a blip. If it is still there plug into OBD port and do diagnostic checks.

Not what I would do but......

Alan

 

[MG4ismyfirstEV]

Maybe. But it could freak out again for no reason too. Dangerous when power drops and braking efficiency takes a nose dive.

Agreed, hence not recommended. However my current confidence of certain dealerships service departments, going by this forum, is not high. With potential software errors I suspect the temptation would be to disconnect/reconnect and take a test drive and if all is clear regard it as a blip. If it is still there plug into OBD port and do diagnostic checks.

Not what I would do but......

Alan

I am taking it back tomorrow to ask kindly they put it on their machines. Meanwhile discussing replacement as an option. It’s only been with me for 3 days out of two weeks. Lol.

 

[Cocijo]

Are you saying that the servo assisted hydraulic brakes don’t work as they should as well as the other issues? Or is just regen affected?

 

[MG4ismyfirstEV]

Are you saying that the servo assisted hydraulic brakes don’t work as they should as well as the other issues? Or is just regen affected?

I don’t know what any of that stuff is. Lol. I know the brakes are brake by wire.

I know that when the fault happened there was no regen at all. At the point of the failure message the brakes seemed very very weak compared to any other car I have driven too.

 

[Cocijo]

I hope that you get it sorted

 

[MG4ismyfirstEV]

I hope that you get it sorted

That and the oil leak.

 

[Cocijo]

Not a great start, but I’m sure that you will enjoy the car once you get over the initial hiccups.

 

[AndyM]

This came up on my display this morning too but not driving. It showed for a couple of seconds then cleared. I was sitting on the drive so didn't notice any limp mode like effects.

 

[MG4ismyfirstEV]

This came up on my display this morning too but not driving. It showed for a couple of seconds then cleared. I was sitting on the drive so didn't notice any limp mode like effects.

Just be ready if it happens on the roads. Take care.

 

[AdeMcG]

Any more instances of this or have the people who reported this had it sorted at a dealer or has it rectified itself?

 

[Swampy]

So, to add to the list of issues on my gorgeous orange MG4.

while on a test run to see if the oil leak issue in the car had been fixed I had the following happen on 4 or maybe 5 occasions.

An alert noise and visible would appear on the screen behind the steering wheel stating vehicle control system fault. At this time the engine power would drop considerably and the cars ability to brake reduced too. Like a limp home mode (zero kers braking available too).

Within seconds another message would appear on the screen, stating Speed Limit Cleared. With that message, all would return to normal.

So, dear MG4’ers, apart from the fact I am going to take it back to the dealers / get it recovered, has anyone else experienced this or knows of it? Is it an easy fix, unlike the oil leak lol.

Just want a car that works.

Thank you all for reading.

View attachment 11909

Hi,
I see at the beginning of your message you said you where on a test run to see if the oil leak had been fixed.
what fix has been done and has it worked?
i see your in the North East. which dealership are you using, Richard Hardie on Silverlinks?

 

[CazandNala]

So, to add to the list of issues on my gorgeous orange MG4.

while on a test run to see if the oil leak issue in the car had been fixed I had the following happen on 4 or maybe 5 occasions.

An alert noise and visible would appear on the screen behind the steering wheel stating vehicle control system fault. At this time the engine power would drop considerably and the cars ability to brake reduced too. Like a limp home mode (zero kers braking available too).

Within seconds another message would appear on the screen, stating Speed Limit Cleared. With that message, all would return to normal.

So, dear MG4’ers, apart from the fact I am going to take it back to the dealers / get it recovered, has anyone else experienced this or knows of it? Is it an easy fix, unlike the oil leak lol.

Just want a car that works.

Thank you all for reading.

View attachment 11909

Can you advise if your fault has been diagnosed? I have just picked up a new MG4, drove 2.5mile then the same fault appeared on my dash. Have spent 5hour sitting in the dealers waiting for them to fix to be told they have no idea what's wrong. So my brand new car has been left with them as they now need to speak to MG.