2024 Trophy ER drivers seat heating fault

[HiFiDave]

Hi All,
I have a Trophy ER (new December 24) and it has developed a strange fault...
Upon unlocking and getting in the car in the morning, the drivers heated seat won't operate. The display chimes when I tap on the seat heating, but the heating symbol won't turn red. Bizarrely, if I press the passenger side seat heating, it chimes too but it does turn red, and with a second tap it goes from high to medium, then to low with another tap, just as my drivers one used to.
I noticed a couple of weeks back it would take maybe a minute for the function to work, but now it's several minutes. ...so after maybe 2-3 miles, it responds, but this fault affects just the drivers seat.
I've also tried the app, setting both seats to heat and a few minutes later when entering the car, the passenger seat is heating but the drivers is not. The app showed 'success' when given the command.
I've not seen any posts on this, so assuming it's not one of the more common faults? Just to clarify, the seat isn't switching to heat, it's not that I'm expecting instant heat from the seat. Have tried a soft reset on the display (it seems to do this sometimes when I get in the car anyway) wondered if anyone had any ideas or fixes, to save me from having to contact a dealer...

 

[ReintjeWA]

I think there was some talk about cable connectors underneath the seat coming loose, resulting in a different fault. Perhaps this is also related to your issue?

I would say a trip to the dealer wouldn’t be unreasonable but I’m afraid the wait time to get in probably will be (unreasonable).

Anyone else been plagued by Airbag Warning messages?

[ Moderator: If you are getting intermittent air bag warnings especially after bumps or moving seats, there is a solution in this post. Edit: Note that there is a clip that can get replaced by the dealer. ] MG4 trophy warning messages. I seem to be getting air bag and tyre pressure warning...

www.mgevs.com

 

[Coulomb]

I think there was some talk about cable connectors underneath the seat coming loose, resulting in a different fault.

I suppose that the computer might be sensing the current drawn by the heater, or lack thereof. But that seems unnecessary outside of a very high end car.

 

[HiFiDave]

It seems to be taking longer every day (from setting off) before the seat heating icon will respond and turn red, was at least 10 minutes/5 miles this morning.
Annoyingly, my nearest dealer is significantly further away than that, so would likely be a 'no fault found' situation when I arrive. So annoying, several little issues already and only had the car 6 weeks...

 

[siteguru]

Is it time after turning the car on, or time after selecting the seat heating option, that the heating starts working?

What if you stop the car, get out and lock it, unlock and get back in - does seat heating work right away or does it show the same issue? (If the same issue then this could be an option if you take it to your dealer).

 

[HiFiDave]

It's time after turning the car on, for the first several minutes whenever I tap the drivers seat heat icon, the display chimes but it stays grey and won't turn red.
When i finished a 20 mile drive this morning, I got out and locked the car. I then unlocked and got back in, the display rebooted as it often (but not always) does, and the button worked first time.
First drive of the day I can reboot the screen or get out, lock, unlock and re-enter and the button does not work.
baffling...

 

[Coulomb]

Is the 12V battery low in voltage perhaps? If so, the car might refuse to use a moderately high 12V draw item until the 12V voltage comes up. Taking longer and longer to come up suggests that the 12V battery is nearly had it.

Perhaps try turning the HVAC fan up high; that's also a high 12V power item. If it then takes longer before the seat heater is allowed on, that's more evidence. Though the DC-DC should probably just pour in more current to compensate for the load, unless it's the DC-DC that is weak.

 

[HiFiDave]

The battery (idle) was at 12.7V before I set off this morning. Fault remained, but passenger seat worked. Turned AC to max temp with max fan speed , radio up and the same, passenger seat turns on but drivers doesn't. About 10 minutes into journey it still wasn't working, then, when stopped at lights I heard a double click from a relay behind me and when I pressed the heat button again, it worked. So assuming relay related (or connections to).
Could be coincidence but will try to listen for this on way home this evening. If anyone knows if there's a relay panel/bank towards the rear of the car or under seat, please let me know so I can investigate further. It's like having an old car again, trying to fix problems...

 

[Coulomb]

The battery (idle) was at 12.7v before I set off this morning. Fault remained, but passenger seat worked

Ah. Of course, the fact that the passenger side works and driver's side doesn't blows my battery voltage theory out of the water. Sigh.

But thanks for doing the tests anyway.

I wonder if the relay for the driver's side heater is loose or the pins corroded. It could be worth finding it and giving it a wiggle and/or inspection. It may be replaceable if necessary, from a car shop.

 

[HiFiDave]

In between bouts of heavy rain I managed to take a look under the drivers seat, in the hope of finding the source of the fault. Sadly all connectors are fitted tight, those that looked like they could be separated and refitted without breaking were done, so it looks like a problem for a dealer to sort out... As the screen is chiming in response to the switch, it doesn't sound like a software fault to me, I did consider doing a hard reset, but that could land me with more problems and nobody but myself to blame. Here's hoping Chapelhouse are as good with MGs as they were with Kias.

 

[HiFiDave]

Just an update...
Did a factory reset from the menu, sadly didn't clear the fault...
Phoned two dealers local (ish) to me, one promised to call back but didn't (and 4 days later still hasn't), the other has booked the car in for 10th March, which was the first available appointment.
I'm sorry if I am sounding increasingly negative, but I just wasn't expecting a fault on a new car and poor comms/long delays when attempting to get it sorted. Rant over!