Suspension fault and flat tires

[ChesapeakeRover]

Last night, coming back from vacation, traveling on the interstate, about a half hour from home, the tire pressure icon appeared. Then seconds later the dash was full of lights and the truck threw a suspension fault, and advised that we do not exceed 30 miles and hour.

We pulled over, four lanes to the shoulder, i got out and confirmed the left rear tire was flat. There was an exit about a 1/4 of a mile a ahead, so we limped on the spare rather than try to fix the flat next to 80 mile an hour traffic.

We pulled into a well lit Burger King and I got the jack and un-winched the spare.

Lucky for me the jack broke halfway though, so somewhat sadly, and somewhat embarrassingly I called Roadside assistance.

After about 20 mins, a 20-something year old showed up in a ford focus, didn't speak much and when he did, I'm guessing he was russian, and he brought a floor jack out of his car, lifted the LR3 up, threw the factory jack aside and then quickly, and i mean quickly, switched the tire out for the spare.

Now to the point in which I'm curious, we obviously hit something while traveling ~80 mph and it punctured the tire, which caused it to deflate.

Now would the fact thar it deflated cause the suspension fault, because of the rapid decrease in the radius of the tire and the suspension wasn't able to adapt so it just freaked and dropped completely?

Just curious

 

[GrahamWelland]

Did the fault go away after the new tyre was fitted?

One thing to watch for is that the suspension sensor wiring is up inside the wheel arch (front at least) and could have been hit by the deflated tyre?

 

[ChesapeakeRover]

After restarting it, and setting the ride height back to normal, it went right back up and was totally normal, no suspension fault anymore.

And the tire that deflated was rear left tire, no wiring harness back there (that I'm aware of)

 

[davez26]

Now would the fact the it deflated cause the suspension fault, because of the rapid decrease in the radius of the tire and the suspension wasn't able to adapt so it just freaked and dropped completely?

That pretty much sums it up.

 

[ChesapeakeRover]

Has anyone changed a flat and replaced it with the donut spare, or just a tire that was smaller in size then the three other tires?

I'm fortunate enough to have the HD package, so when i swapped the tires out, they were identical in size.

Would the suspension 'adjust' itself to the smaller tire, and be somewhat raised at one corner to compensate, or would the truck be leaning over at one corner?

 

[Houm_WA]

This debate has raged on for a while. Even the donut spare has the equivalent outside diameter to the regular tires....there must be a reason for that. I was going to run this experiment myself one day, but haven't gotten around to it!

...for what it's worth I think there would be issues with the TC and other electronic gadgetry before the suspension, but who knows...?

 

[ChesapeakeRover]

Interesting, I would have thought that the spare had a smaller radius than the rest of the tires, but you're right there must be a reason for that, most other donuts i've seen are definitely smaller and thinner, but LR engineers probably figured out early on that they needed the same radius or the EAS would freak.

Oh and one of the lights that lit up if i recall was the Active Roll Mitigation icon and was Red and not Amber... one more piece to the puzzle

 

[Houm_WA]

Are you sure? The suspension fault icon looks like a cartoonage of an LR3 ready to flop!

 

[ChesapeakeRover]

Whoops, my bad... I guess I assumed that a Flopping LR3 would indicate the Roll Mitagation... Excuse my ignorance... it was my first time after all