Brakes didn't work, auto assist didn't work, crashed!

[N2STY]

Can you confirm your car was a MK1

 

[Rocinante]

...

The car has been written off, we asked them to check for faults.
.......
We'll have to wait to see what the insurance uncovers.

Has the insurance company said they will spend time and money investigating the cause ?

 

[Bamboo]

Can you confirm your car was a MK1

Yes.

After @Rocinante pointed me to the other thread, @Tim Green makes the following point suggesting there is indeed a link between the hydraulic brakes and the electronics. this relates back to @Ozzie's and @sgt4hed's
posts earlier in this thread:

Brakes failed

Is there a way to load the dash cam video on this thread or is it photo’s only? I think you have to post to YouTube and link your video here. I hope you get this sorted properly, keep us updated please.

www.mgevs.com

Sorry just trying to help from your 1st post I was thinking it was just a little love tap but now I see your car has been written off it was possible a bit insensitive

No no, all good, finding all suggestions extremely helpful!!!

Has the insurance company said they will spend time and money investigating the cause ?

They have indicated they will investigate, yes.

 

[Seadogs]

Had an issue with an Seat Ibiza where the brake servo stopped working intermittently and then would be fine again. That felt like no brakes at all when it happened but they were on but nothing like normal stopping force.
I had it looked at but sods law no fault found and then the next week it happened again and this time I ran into the back of another car! Sold it immediately after the repair

 

[Rafraf83]

Hi All, well we were loving our MG ZS EV, but we've had a low speed crash, and I tell you , the brakes didn't work! We'd already had some electronic weirdness: the console wasn't switching on, just stayed blank, and a couple of other electronic things went wrong, the lane warning system turned itself off and on while you're driving along. So we had it booked in for a service, but before that, while driving at a low speed in congestion 10mph, had to brake and just nothing happened. What about this automatic crash prevention mechanism?

What happened, I don't know, just slammed my foot on the brake and the thing just sailed forwards into the back of the car in front.

Has anyone else had this failure??

I just had a similar issue with a rental MG ZS. The car was parked in a slight slope. I turned the contact but not the engine (key not fully turned). I usually drive an automatic car, so when I released the hand brake, gear in neutral, and the car started to move, I thought I was an idiot and forgot to press the brake pedal. Then I did press the brake, but it had no effect. And yes, it was the brake, because I double checked by looking at it before the car crushed into the wall. My thinking process was not so fast as to pull the hand brake, though.

 

[fred12345]

I just had a similar issue with a rental MG ZS. The car was parked in a slight slope. I turned the contact but not the engine (key not fully turned). I usually drive an automatic car, so when I released the hand brake, gear in neutral, and the car started to move, I thought I was an idiot and forgot to press the brake pedal. Then I did press the brake, but it had no effect. And yes, it was the brake, because I double checked by looking at it before the car crushed into the wall. My thinking process was not so fast as to pull the hand brake, though.

was this ZS EV or petrol? I can only imagine that the car was in neutral (not P) and brake servo was not on because the car was not "on" ...

 

[Gadget Geek]

I just had a similar issue with a rental MG ZS. The car was parked in a slight slope. I turned the contact but not the engine (key not fully turned). I usually drive an automatic car, so when I released the hand brake, gear in neutral, and the car started to move, I thought I was an idiot and forgot to press the brake pedal. Then I did press the brake, but it had no effect. And yes, it was the brake, because I double checked by looking at it before the car crushed into the wall. My thinking process was not so fast as to pull the hand brake, though.

Er, the ZS EV doesn't have a contact to turn, no engine and no key to turn. I think you're on the wrong forum.

 

[fred12345]

Er, the ZS EV doesn't have a contact to turn, no engine and no key to turn. I think you're on the wrong forum.

sounds like it was petrol ZS ... as far as I remember (wasn't even that long ago!!!) , servo only works when the engine is running ...

 

[Rafraf83]

was this ZS EV or petrol? I can only imagine that the car was in neutral (not P) and brake servo was not on because the car was not "on" ...

It was petrol. The car was “on”, the display was on. Brake pedal should have worked.

 

[fred12345]

It was petrol. The car was “on”, the display was on. Brake pedal should have worked.

not if the petrol engine is not working. on petrol cars, for brakes to work, petrol engine must be running.

I turned the contact but not the engine (key not fully turned).

if you turn the key half-way to contact only, display will be working but not the engine and not brakes.
On electric ZS, when display is on, everything works but on petrol only when the engine is running...

 

[Rafraf83]

not if the petrol engine is not working. on petrol cars, for brakes to work, petrol engine must be running.



if you turn the key half-way to contact only, display will be working but not the engine and not brakes.
On electric ZS, when display is on, everything works but on petrol only when the engine is In theory the brake must run with the hydraulic system regardless of whether the motor is on or off.

That’s a bit surprising. The brakes should work with the hydraulic system regardless of whether the motor is on or off.

 

[fred12345]

That’s a bit surprising. The brakes should work with the hydraulic system regardless of whether the motor is on or off.

it's the same for air-conditioning - it's all connected to the engine, fan will work on contact but cooling (aircon compressor) only when the engine runs. without the engine running, brakes will work only if you apply extreme pressure on the pedal

for brakes to engage without engine running (from experience, it happened to me once that the engine cut off on my old diesel) you have to press really hard - so hard that it feels like you will break the drivers seat pushing with your back against it ...

 

[Lovemyev]

Many ICE vehicles have a brake servo unit that provides the added assistance to the footbrake pedal when pressure is applied / requested by the driver.
The servo chamber is usually charged by pulling a vacuum from the inlet side of engine manifold.
Therefore without the engine running, there is NO assistance provided.
Pressing the footbrake without the engine running, will be extremely difficult and braking efficiency is drastically reduced.
This condition makes braking extremely difficult and can be very dangerous.
Any systems that are boosted or assisted needs to be in a fully operational condition or are extremely difficult to operate.
Power steering is another good example of this.
Without the assistance the steering is almost impossible to operate safely.
EV’s have a brake booster that provides a similar pedal assistance to the driver, but again the car has to be in a condition to drive ( ready mode ) to provide that assistance.