Problems with new (ex-demo) MG4

itm2

We bought an MG4 EV 11 days ago from an Ancaster dealer. It is an ex-demo, first registered in September 2025. It came with a 7 year manufacturer's warranty (6 years still remaining). The day after we collected it we noticed a couple of minor faults: the A-pillar cover by the windscreen had come off, and the dashcam was not powering on most of the time. A week later we noticed a more serious fault: in 34 degree heat the AC wouldn't work - it was blowing out hot air. A reset of the infotainment system managed to stop it blowing hot air, but the air coming out of the vents was now only ambient temperature, maybe a little cooler - not cold.

The following morning, when the temperature was much lower (24 degrees) the problem had gone away, and the AC was back to working normally.

We've arranged to take the car back to Ancaster tomorrow morning for them to take a look (having reported all issues via email as soon as we discovered them). They've said that they will perform an initial triage, and book it in for a formal service appointment if necessary.

We are otherwise very happy with the car, and would like them to fix the problems, but have to consider the possibility that we may need to return it for a refund if they are unable to find and fix the intermittent problem with the AC. I very much doubt that the problem will manifest itself tomorrow morning, as the temperature won't be anywhere near as high as when it happened a couple of days ago. Given that, the dealer probably won't be able to identify the fault, and hence won't be able to work out a solution.

We're mindful of not losing our rights under the Consumer Rights Act 2015, which gives us an option to return the vehicle within 30 days if it is not of satisfactory quality. In the event that they offer us a service appointment in 3 weeks time (i.e. outside this 30 day period), what should we do?

sheenas

The AC issue might be because your driving in eco mode. Many cars restrict the AC in their ECO mode. Change the mode might be all you need to do. Alternatively the refrigerant might need repressurising which they can check. They have one chance to fix the issues, but you might not find it that easy to return as dealer and finance companies are push bad hard on this.

itm2

https://forums.moneysavingexpert.com/discussion/comment/82099321#Comment_82099321

There was an Eco option in the AC settings, which we tried disabling (but it made no difference) - is that what you mean?

My instinct is that the refrigerant levels were not the primary cause, as the AC has been performing perfectly well ever since.

Yes I was wondering how easy it would be to exercise our right to return the car to them, particularly if the service appointment that they offer to try to resolve it is outside the 30-day period.

Woodstok2000

The 30 day period is suspended once you're reported a fault, so the timing of the service appointment isn't a problem. The 30 days restarts once you get the repaired car back. This is the relevant section from CRA 2015:

(6)If the consumer requests or agrees to the repair or replacement of goods, the period mentioned in subsection (3) or (4) stops running for the length of the waiting period.

(7)If goods supplied by the trader in response to that request or agreement do not conform to the contract, the time limit for exercising the short-term right to reject is then either—

(a)7 days after the waiting period ends, or

(b)if later, the original time limit for exercising that right, extended by the waiting period.

(8)The waiting period—

(a)begins with the day the consumer requests or agrees to the repair or replacement of the goods, and

(b)ends with the day on which the consumer receives goods supplied by the trader in response to the request or agreement.

daveyjp

Had you used the aircon all the time before the 34 degrees day?

born_again

A/C sounds like it just needs a regas.

Had a new car with same issue. Tech looked at it said yep needs looking at booked in a week later & they regased. Now nice & cold.

jimjames

A/C sounds like it just needs a regas.

If a car under 12 months old needs a regas it would suggest there is another issue at play that is causing the gas to leak out. It's meant to be a closed system so shouldn't just disappear although if the OP has said the aircon is working fine at other times it would suggest it's not needing regas. Maybe temperature sensor is faulty and not giving correct reading to the system?

daveyjp

If it does need a regas the reason why needs full investigation. I've had regas on a ten year old car as that is all that was needed. When it failed on a 2 year old car it needed a new condenser,

Mildly_Miffed

Anybody else wondering if it's an aftermarket dashcam with the wiring running up the driver's A-pillar…?

My money's on the aircon simply being a settings issue.

born_again

https://forums.moneysavingexpert.com/discussion/comment/82099425#Comment_82099425

Many brand new cars are not fully gassed up due to the cost of doing so. Given the cost of R1234yf short filling can save manufactures millions given the amount of cars produced.

itm2

https://forums.moneysavingexpert.com/discussion/comment/82099367#Comment_82099367

Yes the aircon has been in constant use, before and after the failure. As of today it is still working fine, so this leads me to believe that it isn't simply a regas that's required.