Surfdog
Established Member
And just like the BBC the it looks like the mental health card has been played to avoid answering any questions or giving further explanation."it's on the BBC so it must be true."
And just like the BBC the it looks like the mental health card has been played to avoid answering any questions or giving further explanation."it's on the BBC so it must be true."
The BBC is in the entertainment business, and BBC news is no exception.Just on the subject of "it's on the BBC so it must be true."
That is entirely your perogative and I dont mind at all that youre wrong!You are correct that it may be a much slower speed event than reported, but on the rest I do not agree, johnb80.
Nope, it's easy to have a modulator on the brake lines, essentially pistons in a bore. If the pistons move down the pressure is reduced if they move up the pressure is increased. They would not all fail at the same time dumping all of the hydraulic fluid.If there is a system to "increase a little or decrease a little" the hydraulic pressure, if that system fails then virtually anything can happen,
Why would they use a pressure switch as opposed to a simple mechanical switch on the pedal. The pressure switch is more expensive, harder to adjust, less reliable.it has failed and is out of control. The brake pedal sensor could well be a pressure switch, certainly in older cars it would be very likely, or it could be that the car was "dribbling" as they do at low speed with no accelerator input.
Would you believe, they dont design brake systems this wayAnd what does "they don't design brake systems that way" mean?
Well you'd be wrong there, the design is such that the brake pedal will always transmit pressure to the callipers / pistons. In the event of a leak on one circuit the other circuit will still give some brake functionality.The only way to avoid this scenario is to design a "fail-safe" brake system which would mean the brakes failing in "fully on" mode, as with lorries and buses.
Because it hasnt, it's not necessary for cars.There is no evidence that such a design has been incorporated.
Even if there is no vacuum, servo assisted brakes still work just with a heavier pedal load.The MG ZS EV uses a Bosch electric steering system and therefore COULD be using the Bosch brake I Booster system.
Below is a link to the Bosch web site, for anybody is interested in how the brakes are assisted in an electric car.
Half way down the page there is short video explaining / demonstrating how the system operates.
Vacuum is supplied by an electric motor that is constantly producing a vacuum to keep the servo reservoir top up.
The Tesla system works in a similar way.
Not too dissimilar to the servo unit used in an ICE car, but it this case the vacuum is provided by ICE.
When the reservoir is filled, even if the electric motor looses power, there should be enough stored vacuum to bring the car to a stop.
iBooster
The iBooster is a vacuum-independent and electromechanical brake booster.www.bosch-mobility.com
Well yes, but when did you last drive a car without power assistance? I last did it earlier this year and you end up nearly bending the steering wheel to bring it to a halt when the car is coasting. I'd like to see anyone do it against an EV motor that is trying to maintain the same speed.Even if there is no vacuum, servo assisted brakes still work just with a heavier pedal load.
So explain why the servo failed, and yet the car slowed down to 15mph on a roundabout, even though the MG ZS is notorious for using the brakes to slow on ACC and not regen?Well yes, but when did you last drive a car without power assistance? I last did it earlier this year and you end up nearly bending the steering wheel to bring it to a halt when the car is coasting. I'd like to see anyone do it against an EV motor that is trying to maintain the same speed.
Quite recently by coincidence ?Well yes, but when did you last drive a car without power assistance? I last did it earlier this year and you end up nearly bending the steering wheel to bring it to a halt when the car is coasting. I'd like to see anyone do it against an EV motor that is trying to maintain the same speed.
Yep, the only evidence is what the driver has given us but that can be assessed against experience and knowledge of vehicle systems. Holes in the story were immediately apparent.Dunno, I haven't examined the car or seen diagnostic logs. I do know there are a lot of absolute opinions on this thread with little to no evidence one way or other.
Really? The ECU’s have loads of monitoring and protection systems built in. As an example the throttle is an electrical signal as opposed to a physical Bowden cable in the past. With the Bowden cable if it corrodes or becomes sticky nothing happens other than the engine can be stuck at a throttle setting. On the modern drive by wire systems not one but two signals come from the throttle pedal. If the ECU detects the signals are not identical the ECU will go into a limp home safety mode and will log implausible signal. This type of programming and monitoring is done on most if not all sensors.However plausible or not the story is, there are probably more failure paths in a modern cars computer systems than you can shake a stick at.
Yes John I do agree and understand this fully.Even if there is no vacuum, servo assisted brakes still work just with a heavier pedal load.
Hi. Is the EPB button the central one with R N D which you press to engage handbrake? TiaWithout the power assistance the foot brake is pretty ineffective.
In the MG4 you can use the EPB as an emergency brake in this situation by holding the EPB button up - not releasing it like you would do normally. Not sure if the ZS had this as well.
There would not be much damage if the ZS and the van were doing the same speed then the van slowed after contact was made.
Ok it kind of make sense now, if the ZS lost servo assistant, the brake pedal would be very stiff and hard to press, if the driver was inexperienced, he would have panicked and assumed brake failure??Well yes, but when did you last drive a car without power assistance? I last did it earlier this year and you end up nearly bending the steering wheel to bring it to a halt when the car is coasting. I'd like to see anyone do it against an EV motor that is trying to maintain the same speed.
As I've mentioned earlier in this thread, I used to know him. The picture here is still him, but not a recent picture. Why he wouldn't use his Facebook picture or something more recent is beyond me.Is it me, or is the picture of @MGZS nothing like the picture on the news?! I think that post might be fake, particularly given there have been no further posts since.
I'm sure we'd all love to hear from the real driver to try to understand the full circumstances of what happened.
1) what did the policeman do that deactivated the vehicle?
2) which 9 warning lights came on?
3) where's the car now? With MG?
Based on the news report it all sounds very unlikely, but then sometimes multiple faults can occur simultaneously. Just bad luck?!
You're right. The avatar for @MGZS is not the same guy who features in the news articles and on his Facebook profile. So @MGZS is probably fake or maybe the real guy using another individuals picture. This gets more intriguing by the hour.Is it me, or is the picture of @MGZS nothing like the picture on the news?! I think that post might be fake, particularly given there have been no further posts since.
I'm sure we'd all love to hear from the real driver to try to understand the full circumstances of what happened.
1) what did the policeman do that deactivated the vehicle?
2) which 9 warning lights came on?
3) where's the car now? With MG?
Based on the news report it all sounds very unlikely, but then sometimes multiple faults can occur simultaneously. Just bad luck?!
It is the same guy, but the picture here is about 15 years old!
Saw your post, which was very interesting. I still wonder if the thread post is fake though. You've posted 45 times and I've posted 28, yet neither of us feel the need to create an avatar. Yet this user comes on and creates one straight away with his first post?As I've mentioned earlier in this thread, I used to know him. The picture here is still him, but not a recent picture. Why he wouldn't use his Facebook picture or something more recent is beyond me.
Curiouser and curiouser!Saw your post, which was very interesting. I still wonder if the thread post is fake though. You've posted 45 times and I've posted 28, yet neither of us feel the need to create an avatar. Yet this user comes on and creates one straight away with his first post?
I would not read too much into that little factoid.Yet this user comes on and creates one straight away with his first post?