TJA Warning

Daedalusminos

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Firstly, yes I know there was another thread which is closed and I would have posted this there but wanted to share my experience...

I was using TJA on a straight road - no I mean really straight:
1718962579660.png


Weather was dry and sunny and there was oncoming traffic.

With just my right hand on the wheel loosely gripping it just above the 3 O'clock spoke and TJA set to 60mph but actually travelling at about 45-50mph due to car in front. Yes I know it's not designed for that, that's not the point of this thread.

Without any warning the car swerved very violently left ripping the wheel spoke through my hand, I'm not sure whether it was my reactions or the car that brought it back but it must have been close to clipping the kerb. Then it just carried on, as far as I'm aware the blue lane graphics remained lit throughout.

Just a warning. I wouldn't be surprised if they disable TJA above a certain speed.
 
As you say, TJA wasn't designed to be an "auto pilot" type of mechanism, so any vagaries in operation when used in this manner shouldn't be totally blamed on the car*.

And I've previously reported that TJA has done a similar thing to me on a motorway ... driving in lane 2 and passing a lorry in lane 1 when TJA tried to steer the car into the lorry. That's why I never use TJA now - I'll steer myself TYVM. :)

* well, MG could have coded the software to prevent TJA use above a certain speed if they want to avoid such criticism.
 
I have only ever tried the TJA once, when in a traffic jam and even then it was very poor at keeping the car between lane markings. It was constantly making micro adjustments to the steering when they were not required. From speeds above 20mph I am happy to use the ACC as this seems to be OK with LKA disabled.

As for TJA, I will probably never use it again.
 
TJA only works as Traffic Jam Assist.... Dont use it for anything else.

Any autosteer features of the MG 4 is unreliable.
In your opinion. I've used TJA for lots of motorway driving (with LKA set to middle option) and not had any issues of violent steering pulls etc. It will twitch the wheel if it can't initially understand a change to lane markings, but my previous leased Audi E-tron did that also as a £60k new car.
 
Worked perfectly for me recently in a tailback, 0 to 30 mile an hour shuffle.

Caveat: Arrow straight dual carriageway which was well lit and well lined.
 
I don’t understand why TJA would be used on a straight Norfolk road, with light, fast-moving traffic? I know you say, ‘not designed for this’, so I’m intrigued as to why you would use it in the first place (and I’m sure you have good reasons, can you share?).

fwiw, I’ve never used TJA, I don’t trust MGs engineers to steer the car for me! But I use ACC on the M-Way, where it works quite well, and I’ve occasionally been tempted to use it in slow traffic (although I have to always apologise to any passengers, as it drives like my 14-year-old nephew!)
 
I don’t understand why TJA would be used on a straight Norfolk road, with light, fast-moving traffic? I know you say, ‘not designed for this’, so I’m intrigued as to why you would use it in the first place (and I’m sure you have good reasons, can you share?).

fwiw, I’ve never used TJA, I don’t trust MGs engineers to steer the car for me! But I use ACC on the M-Way, where it works quite well, and I’ve occasionally been tempted to use it in slow traffic (although I have to always apologise to any passengers, as it drives like my 14-year-old nephew!)
The point of the post was that I could use TJA under those circumstances probably means others will use TJA and the fact that I could have caused an accident means others probably will cause an accident.
 
The point of the post was that I could use TJA under those circumstances probably means others will use TJA and the fact that I could have caused an accident means others probably will cause an accident.
Yes, I get it… the point of my reply was, why would you or anyone else use TJA in the first place? Sorry to hijack your post, just curious to know why it would be used in this way.
 

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