MG5 water/moisture in the battery compartment!

Charliecharles250 said:

I bought a MG5 brand new two years ago. In October and November, I had to call the AA three times as the car broke down, saying there was a battery fault.

The car went back to MG Hendy, who identified a thin film of water and moisture within the battery compartment.

MG have said that this is because the car was driven in deep water (which it wasn’t), so not covered by the warranty and that the repair would be £18k! (basically more than the car is now worth).

They’ve stated that they ‘know’ it was driven in deep water because there are leaves on the underside of the car, back of the bumper etc.

And this is despite not other evidence of water damage on the car, no trails of mud/dirt. The water/moisture in the battery compartment is clear, which I believe shows that it entered as vapour.

The car has been looked at independently. The independent engineer has stated that this is a design flaw with the MG5, in that moisture can be sucked into the battery compartment with the changes of temperature. Despite stating this, they have said that it’s not a warranty issue, and I should claim on the insurance. But, I haven’t broken the warranty, as I haven’t driven in deep water, and surely this means they should repair the car, or the car isn’t fit for purpose.

MG Hendy have been awful and so unhelpful to deal with. It’s taken 4 months to get to this point, and they’ve now said they can no longer speak to me, as my views are subjective!

Has anyone else had this problem? Does anyone know anyone who can help?

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Peterboat said:

This is worrying that it's not waterproof, I believe you when you say it's not been wading as we see leaves in back bumpers on service it just happens

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Charliecharles250 said:

The car went back to MG Hendy, who identified a thin film of water and moisture within the battery compartment.

Click to expand...

Charliecharles250 said:

not covered by the warranty and that the repair would be £18k! (basically more than the car is now worth).

Click to expand...

Charliecharles250 said:

They’ve stated that they ‘know’ it was driven in deep water because there are leaves on the underside of the car, back of the bumper etc.

Click to expand...

Charliecharles250 said:

The car has been looked at independently. The independent engineer has stated that this is a design flaw with the MG5, in that moisture can be sucked into the battery compartment with the changes of temperature.

Click to expand...

Charliecharles250 said:

It’s taken 4 months to get to this point,

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MickeySw said:

Modern HV battery packs are waterproof.

That’s an easy fix, open the lid and let it dry out?

That’s most likely the price for a replacement pack, not a repair

The battery is temperature controlled by a liquid medium, not sure what color it is?

The important word here is ‘can’, if this is actually happening commonly, more HV packs would fail.


Opening a HV pack isn’t a trivial operation (assuming that’s how the garage diagnosed the problem), very few dealers have the necessary knowledge, tools and certified technicians.

A somewhat similar case

M

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Hi all,
I mainly need a bit of emotional support and vent. Picked up a brand new MG5 Trophy three weeks ago and am driving it with more care than any car before - never bought a brand new car before this!

Then, one morning this week, I approached a small obstacle in the road. It looked small and I am absolutely not one who is too lazy to get out of the car to move debris out of the way if need be. It looked by far small enough that I could drive over it centrally. Unfortunately, my judgement was wrong. The what turned out to be a wheelie-bin wheel got stuck at an angle under the...

• migros8
• emotional hole mg5 undercarriage vent
• Replies: 26
• Forum: MG5 EV Forum

• 

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Peterboat said:

Unfortunately it appears that this battery pack is letting in water so isn't waterproof, where its come from is the issue. I have heard of leaks on Tesla's batteries through a bad seal, so given the water is clear maybe it's condensation?

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Post in thread 'What depth of water can an Electric Car MG go through?'

Oct 30, 2023

At Fully Charged a senior MG chap told me that the electrics on the car are tested and passed to 1m depth of water. I measured the sills and they are 45cm at the lowest.

I have driven 300mm in the MG5 and did 500mm in a LEAF without an issue.

You must drive slowly due to potential obstructions & underbody protection damage. My front wheel arch covers came off in a flood!

• EVsince2016

• 

Charliecharles250 said:

I bought a MG5 brand new two years ago. In October and November, I had to call the AA three times as the car broke down, saying there was a battery fault.

The car went back to MG Hendy, who identified a thin film of water and moisture within the battery compartment.

MG have said that this is because the car was driven in deep water (which it wasn’t), so not covered by the warranty and that the repair would be £18k! (basically more than the car is now worth).

They’ve stated that they ‘know’ it was driven in deep water because there are leaves on the underside of the car, back of the bumper etc.

And this is despite not other evidence of water damage on the car, no trails of mud/dirt. The water/moisture in the battery compartment is clear, which I believe shows that it entered as vapour.

The car has been looked at independently. The independent engineer has stated that this is a design flaw with the MG5, in that moisture can be sucked into the battery compartment with the changes of temperature. Despite stating this, they have said that it’s not a warranty issue, and I should claim on the insurance. But, I haven’t broken the warranty, as I haven’t driven in deep water, and surely this means they should repair the car, or the car isn’t fit for purpose.

MG Hendy have been awful and so unhelpful to deal with. It’s taken 4 months to get to this point, and they’ve now said they can no longer speak to me, as my views are subjective!

Has anyone else had this problem? Does anyone know anyone who can help?

Click to expand...