Motor Fault - consult handbook

Well, my car has been in for repair for 6 weeks and as of yesterday (Thursday 15th July 2021) the issue was still not fixed. However, today the BCM module was replaced and "fingers crossed" this may have fixed the problem.

I hope none of you out there have to suffer being without your car for as long as I have been, but the Chorley Group have made this as painless to me as possible. They provided me with a courtesy car so I have had minimal inconvenience and they have kept me informed along the way. However, MG service support is in question as to how long it takes to diagnose a complex issue.
 
I have had a similar problem twice in the last week. The first was when I was on my first long journey, I stopped at Scotch Corner to charge, the CCS was in use so I thought I would use the slower charger until the CCS became available. Then a very helpful EV driver told me of another Rapid CCS charger a few miles down the road at Bedale so I uncoupled and went to drive off. Everything was dead and I got a warning to disconnect high voltage. I thought I had done something wrong whilst uncoupling. There was me stuck in a charger space, more than a little embarrassed, when I remembered some advice I got from watching MG EV ZS owners on YouTube, they had said the best investment you can make is to buy a 10mm spanner and put in the glove compartment to allow you to do a hard reset of the car in situations like this. I had bought a spanner for this purpose before my car arrived and had put it into the glove compartment, not thinking I would ever need it. So I got out disconnected the 12v battery for a few seconds, reconnected and tried the car. It started up no problem but the brakes were locked on, so still couldn't move. A warning on the dashboard advised I looked in the handbook and I found a procedure to release the brakes, not sure now what I had to do, except it did say the seatbelt needed to be connected, I had tried a few times without putting the seatbelt on, then tried with it on and away my car went. No more problems on that journey.

However last night my kids decided they wanted a McDonalds so I went to my local drive thru, placed my order and was in a queue of about 15 cars, so I had paid for the food and still in a queue with two cars in front of me taking forever to get served. Finally the front car was served and I needed to move on, this time I had stayed in drive mode but with the automatic handbrake applied, so a different situation than when stopped at a charger and everything switched off. Well the same thing happened, I got a warning on the dash about high voltage, in my panic I didn't have the presence of mind to photograph the warning. But as quick as lightening I got the spanner from my glove box, popped the bonnet catch, disconnected the battery for a few seconds , reconnected and back in the car. Away it went with no brake problem and the car in front was still collecting their order. But it was a horrible situation to be in. Think what would have happened if I hadn't got a spanner with me or known what to do, there was no way anyone could move the car and Mcdonalds drive thru would have been out of operation until a mechanic could get to me.

Not sure what to do now, as this is undermining my confidence in my car that has otherwise been great. Hopefully MG have a fix for this.

I would add that I am very grateful to the fellow owner that had given this piece of advice and would encourage all owners to get a 10mm spanner, hopefully you will never need it but it might just help you our of an embarrassing situation.
 
Tim Green said:
I'm just off to look in my tool kit.......
Click to expand...
It’s one of them !.
If you put the spanner 🔧 in your car, you are not likely to need it !.
But if you don’t, you certainly will !.
I have a 10mm spanner 🔧 in a small plastic Zippy Type Bag, taped to the side casing of my 12 volt battery, just in case.
 
Tim Green said:
I must admit that if I shell out £24K for a new car I do not expect to have to carry a 10mm spanner around! However, I will do it!
Click to expand...
I remember the days, not so long ago, when you used to have to carry your whole tool kit in the boot.
I managed to fit a cambelt to a nephews Vx Nova and a cam belt driven water pump to my Rover 216 during one caravanning holiday to Loch Ness.
 
We definitely have a lot less on our cars these days that require the carrying of a huge tool kit, just in case. But as an old school tinkerer, I don't feel comfortable unless I have at least a basic kit of some description. A few screwdrivers, some spanners, a mini socket set, gaffer tape, a persuader of some description... (I've also got a longer breaker bar, an upgraded set of alloy wheel sockets, a few other random tools). It doesn't take up much space, it doesn't weigh much, and can save a lot of grief. Plus there's always the chance that you come across somebody else needing help.
 
"MG Technical" are about as much use as a chocolate fire guard. I've had issues with my sunroof creaking loudly. It's been off the road for 8 weeks now in total and MG Technical also used phrases like "hopefully it will be fixed"
I replied "hopefully doth butter no parsnips"

My MG dealer is even more dreadful than MG technical. I've already started the rejection process and I get my new Hyundai Kona Electric at the end of the year. I will never consider another MG again.

If I was in your position I would reject the car under the Consumer Rights Act 2015 as unsatisfactory quality.
 
On Friday 23rd July I went to pick up my car. I opened up the car door and the clicking/scratchy sound from the speakers was evident. This was part of the original symptom. Whilst sat in the car I could also see the speedometer & percentage dials flicked by a small amount evey few seconds like some electrical pulse was occurring. When the car was powered on it gave the Motor Fault again. Common pattern is that Friday was an exceptionally hot day.
Also note that I knew it wasn't resolved even before powering on the car. Opening the car door is enough to show the problem exists. So what is alive when the car door is opened and what can be ruled out in this condition?
 
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Opening the car door will begin the wake up procedure - the software will be "on" and looking for the brake pedal depression. It will do security checks on key fob etc.
I suspect you have a software issue.
Make a fuss!
 
Tim Green said:
Opening the car door will begin the wake up procedure - the software will be "on" and looking for the brake pedal depression. It will do security checks on key fob etc.
I suspect you have a software issue.
Make a fuss!
Click to expand...
Thank you for your input to my ongoing issue.
 
My 10 ml spanner it is yellow taped next to the battery..in the bottom of the battery tray.....just like on my Mitsubishi PHEV...better to be safe than sorry.
 
One thing that is significant in my experience with this issue is that the problem is prevelant when the ambient temperature is high. The initial problem occurred back on Sunday 30th May when it was an exceptionally hot day in Dorset. The problem went away later in the evening when the sun was going down. The following morning it was still ok, but as the day warmed up the problem was back again. This was consistent on Monday & Tuesday following the initial problem.

When I went to pick the car up on Friday 23rd July in the afternoon it was a hot day and the exact same fault condition was evident.

So, my feelings are that this issue brought on during exceptionally hot days and will not occur during cooler periods.

Could this be caused by the charge on the 12v battery degrading?

I found the following article from
www.firestonecompleteautocare.com

Does Heat Drain Car Batteries? | Firestone Complete Auto Care

High temperatures can drain us all, and your car battery isnt immune. Check out how heat affects your battery and how you can help it survive summer!
www.firestonecompleteautocare.com www.firestonecompleteautocare.com

HOW SUMMER HEAT ZAPS YOUR BATTERY
Life feels more demanding when it’s hot outside. All of a sudden you need a glass of water after
a short walk around the block! Turns out, your car battery can also get "parched" in the summer.
High temperatures can evaporate your battery's vital liquids and weaken its charge.

What’s more, hot temperatures can speed up the corrosion process. Corrosion will irreversibly
damage the internal structure of the battery, and it’s even worse when your battery is “parched.”

Note that most car batteries are sealed and don't require maintenance. Many do, however, have a
window or water level indicator that will let you see if the water level is good or low.

Then when winter comes, it doesn't have to get too cold to make starting a car difficult for a
heat-weakened battery. Cold kills car batteries, and a heat-damaged battery will go that much
quicker.

The moral of the story? Yes, heat can drain car batteries!
 
Intermittent faults really are the worst. Might be worth investing in a cheapish OBD reader so that you can read the fault codes (if there are any) when the fault occurs. Good point re the battery. Try disconnecting it and measuring the voltage. A healthy one should be 13.5-14V with no load.
I'd be seriously disappointed in the car and very worried about using it in your position.
 
Ok, 2 weeks on from my last update and it's still not fixed. A CAN GATEWAY was replaced but this didn't fix the problem.

It appears that the MG support network is extremely slow to respond and very poor at providing successful action plans. I'm appalled that the diagnostics are not pointing to the actual root cause.

It's been over 2 months since the problem occurred.
 
If you think how much electronic stuff is in cars these days I would not be optimistic about getting to the root of the problem by a swap and test approach.

As you can't be living with a car that has an intermittent problem and they are unable to solve it I think you may have to go down the rejection route.

Or at least threaten that to start with?
 
Another month has passed by and I still don't have my car back (3 months in total). The last action proposed by MG Service Support was to remove the front dashboard and inspect all the cabling. Apparently since all this has been done the problem has not occurred again and it will be tested all this week.
 
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