MG 5 - Car "dies" in traffic queue with manual parking brake applied

[mikeb]

I have a two and a half year old MG5 long range and on two occasions (several weeks apart) I have been waiting in traffic with the manual parking brake applied and when I try to move off (by just pressing the accelerator) nothing happens! I can't be sure but I think the heating fan stops but the instruments are still illuminated. The only way I have been able to "wake" the car up is by turning the car off and then with my foot on the brake repressing the stop start button.

I am just wondering if any one else has had this problem and any thoughts on the way forward would be really helpful. I have thought about taking it to my local dealer but with such a random intermittent fault I am not sure what they could do

 

[5teep]

I often work out of the back of my car (currently the same model as yours) with the power on and I've noticed a few times that if I get in the car and try to drive off it does nothing unless I turn off and on again. I have to say this is long periods, not just sitting at lights so may not be the same issue.

 

[emmrecs]

I wonder if this is because you have used the manual parking brake rather than the Auto Hold button?

My understanding is that the manual brake is there for the normally quite rare occasions when it might be needed. e.g., should it be necessary for any passenger to stop the car's motion in the event of driver illness or incapacity. Pulling and holding the lever in those circumstances acts as an Emergency Braking system

In nearly two years of ownership I don't think I've ever manually applied the brakes with that lever at any time (thankfully no passenger has ever needed to use that emergency system either!).

In the light of what @5teep has just posted, it would seem you are not alone in experiencing this behaviour. Does simply pressing the brake pedal and then the accelerator effect any change?

Also, I believe you can press the parking brake lever downwards and this releases the parking brakes.

 

[mikeb]

Thank you both! Really interesting (except when its happening!) I have tended to favour the manual parking brake over the auto hold button but I will certainly try using the auto hold again; in the past I had found that the auto hold didn't seem to be as smooth coming off but I will try it again. I haven't tried repressing the brake pedal and then the accelerator but I will try that. One final thought which I forgot to mention is that I did try to put the hazard lights on but they wouldn't work - very strange!

 

[emmrecs]

I agree that the release of Auto Hold can be somewhat abrupt when attempting to start off again.

 

[aread2]

I don't like the way the parking brake disengages when it has been applied by autohold. The disengagement after it has been manually applied is smoother. On my pre FL I use the manual parking brake at most stops of more than say, 5-10 seconds. Never had any problem with it disengaging automatically when pulling away again. The difference between auto hold and manually applied brake is odd because I would expect the mechanism to be the same whether the brake was applied manually or automatically. But apparently it's not.

 

[Coulomb]

On my Mark 1 ZS EV, auto hold seems to apply the foot brake, not the parking brake. Releasing the foot brake seems to be quicker and smoother than releasing the parking brake. The parking brake takes longer because there is a motor with a reduction gearbox, you can hear it whirring for about a second when engaging or releasing. With the foot brake, it seems to be a different system, I don't know how it works.

After about 5 minutes of auto-hold via the foot brake, it transfers to the park brake; I hear the sound and the parking brake light comes on.

 

[ozzz]

I have a two and a half year old MG5 long range and on two occasions (several weeks apart) I have been waiting in traffic with the manual parking brake applied and when I try to move off (by just pressing the accelerator) nothing happens! I can't be sure but I think the heating fan stops but the instruments are still illuminated. The only way I have been able to "wake" the car up is by turning the car off and then with my foot on the brake repressing the stop start button.

I am just wondering if any one else has had this problem and any thoughts on the way forward would be really helpful. I have thought about taking it to my local dealer but with such a random intermittent fault I am not sure what they could do

Why do u use the parking brake is it not easier to just put your foot on the brake when waiting

 

[mikeb]

Why do u use the parking brake is it not easier to just put your foot on the brake when waiting

I guess some of it is force of habit and the way I was taught to drive years ago!

 

[5teep]

Why do u use the parking brake is it not easier to just put your foot on the brake when waiting

Not wanting to blind the guy behind me.

 

[Gomev]

Re autohold, I too have found it more abrupt when pulling away....but if you do a quick tap, and I do mean a tap not a push, to the throttle that then releases it and then apply throttle as normal it is smooth.

Not wanting to blind the guy behind me.

In daylight I don't think that's a problem, I've never been blinded by brake lights in a queue in front of me and they are very common.

 

[Coulomb]

Plus, auto-hold will be applying the hydraulic brakes, turning on the brake lights.

For a while I wondered at people in front of me using their foot brakes so much, why not use the parking brake and give your foot a rest. Then I realised that they probably have the equivalent of auto-hold as well. So they probably are resting their feet.

 

[Kompins]

I frequently use Hill Hold in hilly stop start traffic, makes driving so easy. To pull away you need to press the accelerator pedal very gently initially for a very smooth take off.

 

[ozzz]

I guess some of it is force of habit and the way I was taught to drive years ago!

So did I with a stick and clutch, and I still use it in my Kombi but in Automatic never.

 

[Gomev]

I frequently use Hill Hold in hilly stop start traffic, makes driving so easy. To pull away you need to press the accelerator pedal very gently initially for a very smooth take off.

Hill hold is different to Autohold. Hill hold works automatically on inclines when you keep your foot on the brake pedal. The car will maintain the brakes after you lift your foot for a second or two before you hit the accelerator to prevent rolling back.

 

[Kompins]

Perhaps what I really meant was Auto Hold ? Better have a look in the car today!

 

[dragon2611]

I'm not sure if it will do it when just on the parking brake for long enough, but I've had a case where my car was stopped a while in a traffic jam on cruise control and it eventually auto applied the parking brake and took itself out of drive.

You can definitely sit with it in Drive and on the parking brake for a fair while though as I sometimes do especially if it's at night to avoid shining the brake lights into the face of the person behind.

It would be interesting if to see if yours has taken itself out of the ready state entirely or if it's just gone into neutral/park

 

[Deleted member 13103]

I don't like the way the parking brake disengages when it has been applied by autohold. The disengagement after it has been manually applied is smoother. On my pre FL I use the manual parking brake at most stops of more than say, 5-10 seconds. Never had any problem with it disengaging automatically when pulling away again. The difference between auto hold and manually applied brake is odd because I would expect the mechanism to be the same whether the brake was applied manually or automatically. But apparently it's not.

I started using the manual park brake, after reading on here that it works smoother than the autohold, which I fully agree with, autohold release is abrupt, and not pleasant.

 

[PVperson]

I often work out of the back of my car (currently the same model as yours) with the power on and I've noticed a few times that if I get in the car and try to drive off it does nothing unless I turn off and on again. I have to say this is long periods, not just sitting at lights so may not be the same issue.

This is because the car controller will disengage the HV battery, if the car is left for long periods parked with the car switched on (ready to drive) this is for safety, and also to save discharging the battery if the car has accidentally been left switched on.

 

[MickeySw]

This is because the car controller will disengage the HV battery, if the car is left for long periods parked with the car switched on (ready to drive) this is for safety, and also to save discharging the battery if the car has accidentally been left switched on.

Doesn’t make sense to automatically disconnect the HV battery, this will put all the low power load onto the 12V aux and drain it in no time?