Mg M5 EV heater issues

[Chris Harry]

Can anyone help. it now only blows cold air... the dealer fixed it once and said "there was never an issue, it works fine", after some months I went to turn it on and no heat... looked at fuses and its not in eco mode.... is there a reset button that the dealer pressed and it's tripped again ?? Any thoughts?

 

[MickeySw]

Well if you managed not to use the heat all winter, then you should be fine for rest of the year…

Joking aside, you didn’t turn down the temperature too low by any chance?

 

[Jomarkh]

Can anyone help. it now only blows cold air... the dealer fixedit once and said "theer was never an issue, it works fine", after some months went to turn it on and no heat... looked at fuses and its not in eco mode.... is there a reset button that the dealer pressed and its tripped again ?? any thoughts

Hi, what year is the car and is if the newer face-lift model?

 

[Chris Harry]

Hi, its a 72 plate with the fake roof rack.

My wife did say if you lasted the winter why get it fixed..lol

But a couple of times I've actually had to scrap the inside.. not good.

I have checked all controll knobs, nothing seems to work,,,, i bet its me ??!!

 

[dragon2611]

You do seem to need to set it quite high on the pre-facelift exclusive I have unless the cabin is particularly cold, not sure where they're measuring the internal temperature.

It's something Björn Nyland often brings up in his youtube videos that he has to set the temperature a lot higher on several Asian cars than he would on say a German car. Which is odd because 20C should be 20C on any car.

 

[emmrecs]

You do seem to need to set it quite high on the pre-facelift exclusive

Not in my experience!

Mine is a pre-facelift MG5 Exclusive and I rarely, if ever, set the temperature higher than 19 or 20. Or is that level considered "high"?

 

[Alb]

I set mine to 20°C and it works fine.

 

[5teep]

If you turn on front screen clear and turn the heating up to max and get nothing then it's faulty.

 

[Chris Harry]

5teep, just done that, Looks like its faulty then !!

 

[MickeySw]

Look at your battery voltage/amps motor rpm display while standing still, turning on the heat should add about 10-12A (5kW @400V). If it does, the heater itself is working and the issue may be somewhere else in the circuit (heater pump?)

 

[Fluffykins]

Just went to turn on the heater in my 2020 SR 5 Exclusive today (yes I know it's Summer *** but the weather didn't get the memo. We were misting up because it was so cold outside). No heat at all, just cold air. Car not in Eco mode, temp setpoint wound right up to HI.
Heater never has been particularly impressive but never this poor.

Any thoughts any one? Anybody had a similar experience and solved it?

 

[CanyonReveller]

Just went to turn on the heater in my 2020 SR 5 Exclusive today (yes I know it's Summer *** but the weather didn't get the memo. We were misting up because it was so cold outside). No heat at all, just cold air. Car not in Eco mode, temp setpoint wound right up to HI.
Heater never has been particularly impressive but never this poor.

Any thoughts any one? Anybody had a similar experience and solved it?

The misting can come from recirculated air. Try turning off recirculation, enable AC (to dry the air) and turn on the front demister.

As dragon2611 mentions above, I have to have the thermostat set about 4 degrees higher than I would in other cars to get an equivalent temperature.

 

[Fluffykins]

The misting can come from recirculated air. Try turning off recirculation, enable AC (to dry the air) and turn on the front demister.

As dragon2611 mentions above, I have to have the thermostat set about 4 degrees higher than I would in other cars to get an equivalent temperature.

Yeah, turned off recirc, turned on AC.
The thing is, even with the heater wound up through the temperature range until the display switches from showing a temperature setting and just displays "HI", all I get is cold air blowing out.

 

[CanyonReveller]

Yeah, turned off recirc, turned on AC.
The thing is, even with the heater wound up through the temperature range until the display switches from showing a temperature setting and just displays "HI", all I get is cold air blowing out.

The only other thing that comes to mind is checking which vents are selected to deliver hot air. Otherwise, it's probably time for a trip to the stealers.

 

[Fluffykins]

Look at your battery voltage/amps motor rpm display while standing still, turning on the heat should add about 10-12A (5kW @400V). If it does, the heater itself is working and the issue may be somewhere else in the circuit (heater pump?)

The HV heater fuse (47 in the under-dash fusebox, according to my manual) is only rated at 5A

 

[MickeySw]

The HV heater fuse (47 in the under-dash fusebox, according to my manual) is only rated at 5A

Correct, but that seems to be for the heater control unit, same applies to fuse F11 (15A) which, although labelled ‘HV Battery Pack’, is probably for the BMS.

All driver accessible fuses are only connected to the low voltage (12-14V) DC circuit for safety reasons.

 

[Fluffykins]

Thanks. I did wonder about 400V in that area.
Looks like a call to the stealers is in order.
I just hope it's a warranty item

 

[MickeySw]

Thanks. I did wonder about 400V in that area.
Looks like a call to the stealers is in order.
I just hope it's a warranty item

Did you do a ‘hard reset’ already (12V disconnect?).
I just tested my heater, with a present voltage of 375V and heat on Hi, the current briefly reached 15A but then rapidly reduced to between 4-8A and warm air is coming out of the vents.

If yours doesn’t act similarly and fuse 47 is ok then the only thing left is to bring it to a MG dealer for a warranty fix, might want to do this rather sooner than later if you want this working by the time you need it…

 

[Fluffykins]

Hard reset tried, to no effect.
Booked into dealers for August 5th (Dealer could do it earlier but I couldn't as I'd be away).

 

[CanyonReveller]

Let us know how it goes. Good luck!