Not how I thought today was going to pan out...

macd2401

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Stonehouse, Scotland
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MG ZS EV
Drove into work this morning, and just in the last few hundred yards, HV Battery disconnected 🤦‍♂️ Out with the socket set, and the negative lead gets pulled. Wait for while, reconnect, everything that should clunk did so, and off we went. No big deal thinks I.


Finished my work, and heads off. ¼ of a mile later...same again. And again, and again 🤦‍♂️

Let's see how this pans out. MG Assistance on the way.
IMG-20220217-WA0003.jpeg
 
I see it sometimes when I'm too quick for the system when starting and selecting D or R before READY is fully displayed. Slowing down and starting again always works. This seems like a new development so you were moving when it happened? I have had it once where I had to put in N and push car (5SR) out of way of other traffic but I was static in queue of cars at the time press the go pedal and that caption came up and it would not go even with the classic switch it Off and On again. Bad luck hope all works out well. Interesting that the AA Man didn't have a quick fix as he will have some EV experience? Keep us all informed please.:sick:
 
Drove into work this morning, and just in the last few hundred yards, HV Battery disconnected 🤦‍♂️ Out with the socket set, and the negative lead gets pulled. Wait for while, reconnect, everything that should clunk did so, and off we went. No big deal thinks I.


Finished my work, and heads off. ¼ of a mile later...same again. And again, and again 🤦‍♂️

Let's see how this pans out. MG Assistance on the way.View attachment 7023
I hope that you get it sorted. Exactly what happened when you say hv battery disconnected? Any warning lights? Loss of drive? Loss of all power?
 
Just in the door.

Bearing in mind, it's MG Assistance that were contacted.

AA recovered me to MG Rutherglen. They'll get to it when they can, and will try to put a rush on it, but they're quite busy.... :( Ok, that's not a good start.


Oh yeah, and they also have nothing to do with the courtesy car, and anyway, all of theirs are booked out well in advance... :( Looking a bit iffy now.

AA fella calls his control to get something sorted, because that's part of the package, and drives me home in the meantime.

Missed a call from Enterprise because my phone was dead. Called them back. Yup car hire can be sorted, if I'm ok to pick it up on Saturday. Not perfect but looking brighter...

That's great, and we'll need it back by Tuesday. Wait. What??

Yeah, it's only 72 hours hire.

That's great, but the woman at the dealer mentioned a lot longer than 72 hours...March was mentioned...

Hmm, well, we only do 72 hours, maybe your insurance company can sort something after that point :( :(

Suddenly this isn't looking too rosy at all...
 
I hope that you get it sorted. Exactly what happened when you say hv battery disconnected? Any warning lights? Loss of drive? Loss of all power?
Was stopped at lights, and when I went to move away, there was no power. Fault lights for HV battery and I think a general fault (Red, exclamation mark inside either battery or a triangle (it was daft am this morning))

When it happened again after I left work, it happened whilst moving. Loss of HV battery, Vehicle Control System fault on the centre display, same array of warning lights.

Got it cleared again, but it happened again multiple times.

On the upside, when the traction battery disconnects, it freewheels to a stop... on the downside, once it stops, it puts the handbrake on, so you're stuck there.
 
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What was the voltage showing for the 12v battery?

Seen this type of thing multiple times on the Pug forum and has been (cheap factory fit) 12v related.
Haven't put a meter on it for a while, and I'd be lying if I said I can remember exactly what it was showing at the time. Don't recall noticing any large changes on the meter of late.

I do remember there were a few 12V battery failures a while back, and all with the stock items, which this one has fitted. I'm not going to be overly happy if that's what it turns out to be 🤦‍♂️
 
I think the A.A. will set you up with a hire car ASAP, to get you up and running, while the dealer takes a look at your car.
If it is decided that it is not a quick fix, the dealer will get in touch with the MG after sales team, to give permission to authorise another hire car, from a local firm, or even extend the loan on the one you have.
It is very unlikely to be a EV and the dealer is very unlikely to loan out one of their cars.
This is what happened when we had our car recovered to the dealer by the A.A. when our handbrake on the ZS EV would not release.
The hire company gave us a 2019 "Pug 3008 Derv" and we had it for just short of one month.
 
Haven't put a meter on it for a while, and I'd be lying if I said I can remember exactly what it was showing at the time. Don't recall noticing any large changes on the meter of late.

I do remember there were a few 12V battery failures a while back, and all with the stock items, which this one has fitted. I'm not going to be overly happy if that's what it turns out to be 🤦‍♂️
@macd2401 see this thread...

 
I think the A.A. will set you up with a hire car ASAP, to get you up and running, while the dealer takes a look at your car.
If it is decided that it is not a quick fix, the dealer will get in touch with the MG after sales team, to give permission to authorise another hire car, from a local firm, or even extend the loan on the one you have.
It is very unlikely to be a EV and the dealer is very unlikely to loan out one of their cars.
This is what happened when we had our car recovered to the dealer by the A.A. when our handbrake on the ZS EV would not release.
The hire company gave us a 2019 "Pug 3008 Derv" and we had it for just short of one month.
I remember the problems you had back then. Not their finest hour.
 
I've just had a look through my tracker logs for yesterday (and also today, no movement of the vehicle, zero surprises :cautious:)

If I'm reading them correctly, it would appear that the 12V system was hovering around the 13.9-14V mark for most of the journey, and then dropped to c12V around the time of the first shut off, and possibly even lower (updates are roughly 30 seconds).

When I left work, it again shows the voltage as being between 12.4 and 14.4V until the next series of failures, where it varies wildly.

Looking at the feed from the car just now, it's sitting at 12.61V, and the only thing drawing any power (that didn't come with the car) is the tracker unit :unsure:

At the time, I did try scanning the car for faults (as did the fella from the AA). He found nothing, I found nothing relating to the power, only one or two things about the TPMS and rain sensors not reporting.
 
I've just had a look through my tracker logs for yesterday (and also today, no movement of the vehicle, zero surprises :cautious:)

If I'm reading them correctly, it would appear that the 12V system was hovering around the 13.9-14V mark for most of the journey, and then dropped to c12V around the time of the first shut off, and possibly even lower (updates are roughly 30 seconds).

When I left work, it again shows the voltage as being between 12.4 and 14.4V until the next series of failures, where it varies wildly.

Looking at the feed from the car just now, it's sitting at 12.61V, and the only thing drawing any power (that didn't come with the car) is the tracker unit :unsure:

At the time, I did try scanning the car for faults (as did the fella from the AA). He found nothing, I found nothing relating to the power, only one or two things about the TPMS and rain sensors not reporting.
Trackers can be a pain sometimes draining the 12v battery, its a problem I had on my motorcycle. If the car is only being used for short times or journeys for example and only being charged once a week from a wall box the 12v battery isn't being recharged enough but the tracker is drawing current 24/7. The same can happen on ICE cars. And with dash cams if they are left on all the time
 
Trackers can be a pain sometimes draining the 12v battery, its a problem I had on my motorcycle. If the car is only being used for short times or journeys for example and only being charged once a week from a wall box the 12v battery isn't being recharged enough but the tracker is drawing current 24/7. The same can happen on ICE cars. And with dash cams if they are left on all the time
I did about 15000 miles in my first year, sitting still ain't the problem :LOL:
Dash cam is on a circuit that cuts out if the supply voltage drops. But now you mention it, the dash cam had switched off when I started up after work. Car park at work is underground, so I don't have any data for that period.
 
That still shouldn't have caused this issue because at the time the HV battery should have been charging the 12v battery. There must be some sort of transformer/smart charger and perhaps that could be faulty?

The 12v battery has to be able to hold open the HV battery relays and contactors, so if this drops (due to charger fault on car) maybe it didn't have enough juice to keep the relays (which will then be connected to contactors) open?
 
Does the warranty cover hire car?

If not that's a big, big worry!


@macd2401 ? Could this be a similar issue to yours? Just a thought.

 
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