When drive means reverse?

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So, an interesting thing happened this afternoon.

After a week away, we put the luggage in the car at the airport, reversed, engaged drive and…. Reversed.

Ok, neutral, drive, and….reversed.

Third times the charm. This time, reverse, neutral, drive, and….reversed.

In the middle of the car park, we switched the car off, restarted it and drive engaged.

Also haven’t been able to MG smart for the past few days. Anybody else been having fun with their car?
 
BadGolf said:
So, an interesting thing happened this afternoon.

After a week away, we put the luggage in the car at the airport, reversed, engaged drive and…. Reversed.

Ok, neutral, drive, and….reversed.

Third times the charm. This time, reverse, neutral, drive, and….reversed.

In the middle of the car park, we switched the car off, restarted it and drive engaged.

Also haven’t been able to MG smart for the past few days. Anybody else been having fun with their car?
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This happens with ours occasionally, it just randomly won't select a drive gear. Switching it off and on again resolves.

All part of the charm of MG's software/firmware QA I suppose?

I've been asked to keep it positive.
 
Bodgerx said:
This happens with ours occasionally, it just randomly won't select a drive gear. Switching it off and on again resolves.

All part of the charm of MG's software/firmware QA I suppose?

I've been asked to keep it positive.
Click to expand...
I really want to like it, and be positive. Not at the safety of my children though.
 
BadGolf said:
So, an interesting thing happened this afternoon.

After a week away, we put the luggage in the car at the airport, reversed, engaged drive and…. Reversed.

Ok, neutral, drive, and….reversed.

Third times the charm. This time, reverse, neutral, drive, and….reversed.

In the middle of the car park, we switched the car off, restarted it and drive engaged.

Also haven’t been able to MG smart for the past few days. Anybody else been having fun with their car?
Click to expand...
Does it display the D for drive engaged on the selector and the dash and then still reverse?
 
I'm assuming the electric motor is reversed..
If that is correct, there must be a changeover relay or contactor.
It could be that part is sluggish or sticking.
Dealer....
 
If it's taken to the dealer it's odds on they will say they've checked it over and can find no faults.
Would have been a good idea to video the experience on your phone as evidence.
Hindsight is a wonderful thing.
 
Cocijo said:
Does it display the D for drive engaged on the selector and the dash and then still reverse?
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It did. And the forward cameras came on to indicate it was in drive also.
 
That makes sense if the contactor is sticking: the logic is doing the correct thing but the contactor is not changing.
You could try putting it in Park between D and R as this might help....or not.
As it is quite unsafe as it is I think you should take it back.
As the contactors are handling high voltages and currents it is likely they have had similar faults before.
 
It won't have a reversing contactor, it will have solid state controls, eg some type of transistors in a bridge arrangement
It's sounding like a software bug to me
 
Well obviously the dc-ac motor drive will use a high power bridge, and they could just use that. However the results of any confusion in drive protocol would be so catastrophic that some sort of separation would probably be sensible.
 
Tim Green said:
Well obviously the dc-ac motor drive will use a high power bridge, and they could just use that. However the results of any confusion in drive protocol would be so catastrophic that some sort of separation would probably be sensible.
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That's overcome in industrial applications by having 2 very distinct disable circuits, commonly known as "safe off", it gives the drive a safety rating similar to physical disconnection

Disconnecting the output stages of any drive connected to an AC asynchronous motor is a big "no, no" the drive can be irreparably damaged due to the surge caused as the magnetic field collapses, and just as importantly, this can cause the disconnecting device to weld shut. Which is why most controls have physical disconnects on the incoming and electronic disablements on the outgoing

Of course this is all just supposition, I'm trying to apply my knowledge on industrial motor controls to a different application
 
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I'm in the same position, mainly worked with PSU's and induction cooking systems.....nothing to do with motors really. More to do with getting peak power into a coil.
I have found the motor control system very sound so far, but there can always be glitches I suppose...
There is obviously a contactor as the main battery disconnect, but that does not seem to be used when changing direction of travel.
 
There is of course another even bigger danger here.
If it is possible to drive the car when the opposite direction is selected then if it were to revert back to the selected direction during driving that could have disastrous effects.
For example, selecting reverse and getting forward drive and driving off with reverse still selected, only to have reverse engaged later by the car at speed while going forward.
Unlikely, but with what seems like a failsafe issue, possible.
 
A very good point, except that if what you select doesn’t happen, you tend to know about it.
The car should go to the garage until sorted.
 
Tim Green said:
A very good point, except that if what you select doesn’t happen, you tend to know about it.
The car should go to the garage until sorted.
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Pretty good for less than 1,000kms
 
Something similar has happened to me a few times. I had thought that I must have done something weird somehow and didn’t really think about it. But a few weeks ago I had the car parked, got back in, switched on, put it in drive, pressed the accelerator and very nearly reversed in to the car behind me. I ended up turning the car off and starting the whole process again.

The next time it happened was in the driveway at home and at this point I’d realised it was the car, not me! I experimented with it and went backwards a few times and quite a distance (I would say 2m??) before the car decided to go forward.

It only happens when I have reversed it in to its parking spot.
 
BadGolf said:
So, an interesting thing happened this afternoon.

After a week away, we put the luggage in the car at the airport, reversed, engaged drive and…. Reversed.

Ok, neutral, drive, and….reversed.

Third times the charm. This time, reverse, neutral, drive, and….reversed.

In the middle of the car park, we switched the car off, restarted it and drive engaged.

Also haven’t been able to MG smart for the past few days. Anybody else been having fun with their car?
Click to expand...
were you on a slope? I parked car switched off got out then decided to park a bit better. got back in & started. put car in d & it went backwards. found out later that drive doesn't engage if drivers safety belt not on! So car kept rolling backwards - in my panic I think I also must have taken handbrake off with switch.
 
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