Software update pre-heater relay

nem

nem

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Just got a call from my dealer regarding an imminent recall for software update concerning a pre-heater relay that might heat up and get damaged.
I dont use the pre-heater myself as i mainly charge at home, but figured since i havent seen anything regarding this here that a warning is appropriate.

Dealer said a letter from MG is coming soon, and the software update (which apparently isnt OTA) will take approximately 15 minutes to complete at the garage.
This might be region specific, i dont know, but i doubt it unless there are markets that doesnt have a pre-heater..

EDIT: I didnt put the word "recall" in the title as i dont really know if its an official recall or not.. But kinda sounds like it?
 
Yeah this is related to the pre-heater relay, for pre-heating the battery pack before charging. Not sure if its connected to the heatpump but i suspect it might be. And then it wouldnt be relevant for the UK customers at least.
 
Two instances of cars catching fire in Norway in connection with battery preheating. Just got a call from the garage saying I should not use the preheat function and that I will be getting a call to arrange an appointment for the software upgrade.
 
The message from various delarships here in Norway is adressing a software issue related to the heat pump and fan malfunctioning, not the battery itself, or at least that was what my dealership told me.

The error may affect the (pre)heating function under certain conditions. Until the vehicle has received a quick software update, we recommend the following precautionary measures:

- Avoid pre-heating via the iSMART app.

- Do not heat the vehicle in "READY" mode while unattended.

- Ensure that no one remains in the vehicle with the heater on while unattended.

- Avoid indoor parking or parking adjacent to buildings while the car is heating up or in "READY" mode.

There has been at least 4 fires, and also several cases of heavy smoke development that have been stopped before developing further.

Pretty serious situation in which I am sure MG and the importer is working overtime to fix as soon as possible.
 
Well that's even more serious than what my dealer told me.

Do we have any links with concrete information about this? I use the app to preheat the cabin, every day.. Kinda getting worried now.
 
The info I have is from the Norwegian MGS5 group on Facebook. There's been quite a bit of discussion about this situation today and several have shared the info they have from various dealerships. I've been in contact with mine and they confirmed what's been shared. Avoid preheating the car from the app. Monitor the car closely if you turn it on and have it in ready state to warm the car up before driving. There's not supposed to be any danger connected with regular driving, just the preheating phase. You will be contaced by both Norwegian Mobility Group (importer) and your dealership. Your car will be scheduled for a software update in very near future.
nem said:
Well that's even more serious than what my dealer told me.

Do we have any links with concrete information about this? I use the app to preheat the cabin, every day.. Kinda getting worried now.
Click to expand...
 
According to an email from the Norwegian importer, you can remove a fuse to relieve the problem temporarily. It's the fat one marked 40 on the top right of the fuse box. There's still heating.

Wonder if recall soves the problem with the extremely noisy fan action going on...
 
Yeah i saw, fuse no 13.
I dont think this will affect the fan noise but we will see. I will remove said fuse today as i use the cabin pre-heater rather often..
 
Sounds like a very worrying problem. No menthion of this within the UK yet. Doesn't mean its not an issue though.
 
nem said:
Yeah i saw, fuse no 13.
I dont think this will affect the fan noise but we will see. I will remove said fuse today as i use the cabin pre-heater rather often..
Click to expand...
Removing the fuse definitely removed the extreme fan noise. I really hope it doesn't return after the fix! In my opinion that noise ruins the car.

But what does removing that fuse even do? Stop the heat pump from running?
 
Interesting..
I dont really know, I guess there should be a fuse list somewhere explaining what they are for..
 
tor said:
Removing the fuse definitely removed the extreme fan noise. I really hope it doesn't return after the fix! In my opinion that noise ruins the car.
Click to expand...
That's interesting. In the UK although you can hear the fan I wouldn't describe it as noisy. It looks like it's heat pump related.
 
Indeed the recall notice specifically states it's only concerning cars with heat pump. I've always seen the heat pump as the culprit. The noise seems to originate from "deep" within the front, where the pump presumably is located. With this fuse removed, I only hear some faint fan sounds from the "dashboard section".
 
tor said:
I found a user manual online, it says "cooling fan".

Bruksanvisning MG S5 EV (2025) (351 sider)

Manual MG S5 EV (2025). Se manualen for MG S5 EV (2025) gratis, eller still spørsmål til andre eiere av MG S5 EV (2025).
www.bruksanvisningpdf.no www.bruksanvisningpdf.no
Click to expand...
I guess you got yours from Fredrikstad Autocenter? They called me yesterday regarding this problem but i did not get any time for when to fix so i guess i will remove fuse 13 tomorrow.
 

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