WARNING: Counterproductive "safety" features.

[Ron50]

After my experience yesterday I'll never be able to fully trust my Grenadier again.

I had enjoyed trying out the car in steep terrain and found that I hadn't needed to use low range or lockers but had switched on Off Road mode anyway.

When I got onto a major road that was still unsealed I watched to see that the Off Road mode had cancelled with increased speed - as it is supposed to.

As I approached a minor right hand kink on a fairly straight bit of road the car suddenly decided it could do a better job of driving than I could, slammed on the brakes and sent me into a ditch.

I had mown down a couple of flexible plastic posts but no real damage was done. However the steering now veers right slightly and the steering wheel is a few degrees off to the right. I'm hoping a wheel alignment will be all that is needed to correct this as I can't see anything bent or out of place in the front end.

I can't be sure whether it was the autonomous emergency braking, stability control, ABS or a combination that caused the car to go haywire for no obvious reason but it has destroyed my faith in the electronic "safety" aids of the Grenadier.

Perhaps if I had switched off the stability control as I always did on my Pajero on unsealed surfaces this would have prevented the problem - that is, if it doesn't automatically switch back on above 70kph in the same way Off Road mode switches off above that speed.

The stability control effect on the ABS on the Pajero made it feel as if the brakes had failed on loose surfaces, especially in 2WD, which is why I turned it off when I remembered.

Has anyone else had a similar experience?

 

[landmannnn]

After my experience yesterday I'll never be able to fully trust my Grenadier again.

I had enjoyed trying out the car in steep terrain and found that I hadn't needed to use low range or lockers but had switched on Off Road mode anyway.

When I got onto a major road that was still unsealed I watched to see that the Off Road mode had cancelled with increased speed - as it is supposed to.

As I approached a minor right hand kink on a fairly straight bit of road the car suddenly decided it could do a better job of driving than I could, slammed on the brakes and sent me into a ditch.

I had mown down a couple of flexible plastic posts but no real damage was done. However the steering now veers right slightly and the steering wheel is a few degrees off to the right. I'm hoping a wheel alignment will be all that is needed to correct this as I can't see anything bent or out of place in the front end.

I can't be sure whether it was the autonomous emergency braking, stability control, ABS or a combination that caused the car to go haywire for no obvious reason but it has destroyed my faith in the electronic "safety" aids of the Grenadier.

Perhaps if I had switched off the stability control as I always did on my Pajero on unsealed surfaces this would have prevented the problem - that is, if it doesn't automatically switch back on above 70kph in the same way Off Road mode switches off above that speed.

The stability control effect on the ABS on the Pajero made it feel as if the brakes had failed on loose surfaces, especially in 2WD, which is why I turned it off when I remembered.

Has anyone else had a similar experience?

Useful post.

In practice, ESC is not ideal on loose surfaces. If it detects slide it will react in a way that works on sealed surfaces but not so good where the surface has limited grip.

ESC off would be the best choice, it does stay off BTW.

A Defender for example has a grass/gravel/snow mode, I would assume that this turns off ESC or at least changes the parameters.

 

[Ron50]

Useful post.

In practice, ESC is not ideal on loose surfaces. If it detects slide it will react in a way that works on sealed surfaces but not so good where the surface has limited grip.

ESC off would be the best choice, it does stay off BTW.

A Defender for example has a grass/gravel/snow mode, I would assume that this turns off ESC or at least changes the parameters.

Thanks for that: really good to know the ESC will stay off. I couldn't determine this from the owners manual.

Maybe I'll be able to gain some trust in my car down the track.

 

[Tinerfeño]

However the steering now veers right slightly and the steering wheel is a few degrees off to the right. I'm hoping a wheel alignment will be all that is needed to correct this as I can't see anything bent or out of place in the front end.

Not an alignment problem. Most probably drag link or track rod has been bent. I would check this asap.

 

[Phred]

So off-road mode takes ESC to ESC off-road.

Could it have been the truck hitting the proper speed and turning off OFF-ROAD mode, then ESC off-road switched to full ESC? And that caused ann issue since you were on gravel maybe slipping in the corner?”

 

[Michael H.]

From the manual …

 

[Michael H.]

Also, Robert Pepper advises against turning ESC off for high speed dirt road driving.

 

[Ron50]

Could it have been the truck hitting the proper speed and turning off OFF-ROAD mode, then ESC off-road switched to full ESC? And that caused ann issue since you were on gravel maybe slipping in the corner?”

I had wondered about this too but I had definitely been watching for the speed at which Off Road mode turned off automatically. However, the incident happened only a kilometre or so after Off Road mode turned off.

Maybe normal mode has a grace period before applying fully for exactly the reason that going from off to on in the middle of a corner could cause problems. I'd estimate that I was travelling at 80 to 90 kph and was sliding a bit but less than I had on previous sections of the road that were tighter. I'd even thought about how well balanced the car was in those conditions. The Grenadier is a 12 years newer car than the Pajero so improvements in the electronics would be expected.

 

[Ron50]

From the manual …

View attachment 7881913

Interesting. My manual (for a 2023 model) gives the speed as 44 mph or 70 kph. Is your quote for a 2024 model?

 

[Michael H.]

Interesting. My manual (for a 2023 model) gives the speed as 44 mph or 70 kph. Is your quote for a 2024 model?

The quote was from an electronic version of the manual that I downloaded last year.

I just checked the paper version that I got with my car in July 2023, and I can’t find any reference to the speed at which ESC re-activates.

 

[Ron50]

The quote was from an electronic version of the manual that I downloaded last year.

I just checked the paper version that I got with my car in July 2023, and I can’t find any reference to the speed at which ESC re-activates.

On the electronic version I downloaded recently it is on page 95, third paragraph, in italics.

In my paper version it is on page 106.

But your quote is referring to ESC off mode and my reference of to switching from Off Road mode to normal mode.

This is at variance with landmannnn's advice/experience:

"ESC off would be the best choice, it does stay off BTW."

 

[Michael H.]

On the electronic version I downloaded recently it is on page 95, third paragraph, in italics.

In my paper version it is on page 106.

That's when off-road mode disengages.

ESC OFF disengages at 78km/h (page 102 of the electronic version).

 

[Ron50]

That's when off-road mode disengages.

ESC OFF disengages at 78km/h (page 102 of the electronic version).

Yes, I didn't see your response before editing my reply. Have you tested this on your car? Perhaps your download is from the US manual. Page 113 of my Australian paper manual doesn't give a disengagement speed.

I hope landmannnn is right and the English or Australian versions stay disengaged above 78 kph.

I'll certainly try it next time I drive and will report back.

 

[Michael H.]

I disagree that switching ESC OFF is a good idea on dirt roads. I don't know if you’re familiar with Robert Pepper's work, but he advises against it too. I’ll see if I can find a reference to his advice on the subject, but right now I’m going to get the mowing done before it gets too hot.

 

[landmannnn]

Yes, I didn't see your response before editing my reply. Have you tested this on your car? Perhaps your download is from the US manual. Page 113 of my Australian paper manual doesn't give a disengagement speed.

I hope landmannnn is right and the English or Australian versions stay disengaged above 78 kph.

I'll certainly try it next time I drive and will report back.

I need to double check!

 

[Ron50]

I disagree that switching ESC OFF is a good idea on dirt roads. I don't know if you’re familiar with Robert Pepper's work, but he advises against it too. I’ll see if I can find a reference to his advice on the subject, but right now I’m going to get the mowing done before it gets too hot.

I've seen his YouTube stuff. As I mentioned, my experience with the Pajero leads me to think otherwise.

The cutting of power on uphill tight corners is just an embuggerance but the backing off of the brakes when one wheel locked was downright dangerous. I want a car to react consistently and not override my inputs with its own.

My wife bought a new Mazda 3 that I now have to drive because she has been spooked by the electronics package. I've actually got out to apologise to drivers who have nearly rear-ended me because I've slowed a little faster than usual and the emergency autonomous braking has thrown the car into panic stop mode.

 

[Michael H.]

I've seen his YouTube stuff. As I mentioned, my experience with the Pajero leads me to think otherwise.

The cutting of power on uphill tight corners is just an embuggerance but the backing off of the brakes when one wheel locked was downright dangerous. I want a car to react consistently and not override my inputs with its own.

My wife bought a new Mazda 3 that I now have to drive because she has been spooked by the electronics package. I've actually got out to apologise to drivers who have nearly rear-ended me because I've slowed a little faster than usual and the emergency autonomous braking has thrown the car into panic stop mode.

I’m still wondering whether ESC caused the issue you had.

In your first post, you said that the car “slammed on the brakes” and this post mentions “the backing off of the brakes when one wheel locked”.

It's a pity cars don’t have something like flight data recorders so we could analyse what happened.

The most important thing is that you’re OK.

 

[scottyboy436]

Sounds like not driving to road conditions is the issue, unsealed roads , driving over 40mph in a 2.8tonne vehicle.

Just glad your okay