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Ferengo
24th May 2009, 11:12 PM
Was driving along last night and this warning light came on. So, stopped in the local Tesco and got the manual out. Turns out I may have a flat tyre so I checked the pressures and sure enough I had one that was low. Pumped it up and reset the warning light. The warning light came back on and won't go off. My questions is though, does the R56 as a standard have this low tyre sensor? I never thought I did, was a bit of a shock.

Craig
25th May 2009, 09:53 AM
Grant - it's a sensor in the hub checking the speed of rotation. I think all MINIs that were supplied with run-flats have to have them. ;)

Ferengo
25th May 2009, 05:51 PM
Grant - it's a sensor in the hub checking the speed of rotation. I think all MINIs that were supplied with run-flats have to have them. ;)

That's the thing I don't have run-flats nor have I ever had them :confused:. standard 15" Spoolers.

GCA3N
25th May 2009, 07:08 PM
Grant - it's a sensor in the hub checking the speed of rotation. I think all MINIs that were supplied with run-flats have to have them. ;)


Craig is that correct about the run flat indicator. I was in an alloy shop today:eek: and i asked if my run flats could get put on some alloys i was looking at. The guy said that when you remove the tyre is ruins the valve's. He went on to say that it was this that sent a signal to the car to tell it if the tyre was flat, and then said if i wanted to use my tyres it would add £150 to the cost. Needless to say i left promply, what exactly is this guy on about any ideas.

Duncan Stewart
25th May 2009, 07:38 PM
All my new Minis have been supplied with runflat indicators (two R50 and a R56) I think they all have them as standard.

Scottie
25th May 2009, 07:51 PM
Craig is that correct about the run flat indicator. I was in an alloy shop today:eek: and i asked if my run flats could get put on some alloys i was looking at. The guy said that when you remove the tyre is ruins the valve's. He went on to say that it was this that sent a signal to the car to tell it if the tyre was flat, and then said if i wanted to use my tyres it would add £150 to the cost. Needless to say i left promply, what exactly is this guy on about any ideas.


that's is not the correct information for the Mini.

What the guy was talking about is the TPM system that can be found in Jeeps, Chryslers and other 4x4's.

However you can swap the valve from wheel to wheel although not many fitters are willing to this but as these valves and like £70 each hence Allan has generally changed them over.



My mini has the runflat indicator as standard the car did not come with runflats fitted.

Craig
25th May 2009, 08:41 PM
aye greig, the guy was pulling yer leg... or trying to con you... :argh:

I thought all cars had the run flat indicator, but didn't want to be wrong.. ;)

GCA3N
25th May 2009, 09:30 PM
aye greig, the guy was pulling yer leg... or trying to con you... :argh:

I thought all cars had the run flat indicator, but didn't want to be wrong.. ;)


Yeh i thought so.

The Dogfather
25th May 2009, 11:15 PM
The tyre warning will also fire up if you have too much pressure as well. I had a new front tyre fitted not that long along, was bombing down the A1 just after it was fitted, it went off. Turned out the tyre was 3psi higher than the other front.

Ferengo
26th May 2009, 08:01 AM
Ah, So they all have it. Cool. Well off to get a new tyre now :thumbs up:. Cheers for the help :D.

Big Gordy
26th May 2009, 08:43 AM
The run flat indicator is linked to the ABS. The sensor in the ABS checks the rotation of the wheels. When the tyre pressure changes, the rolling circumference of the tyre changes ie soft tyre=smaller circumference=faster rotation, harder tyre =larger circumference=slower rotation. It then works out the differences between the wheels and if it falls outwith the ECU's parameters that's when the warning light comes on:thumbs up:
So endeth todays lesson children:idea::moonie:

GCA3N
26th May 2009, 10:43 AM
The run flat indicator is linked to the ABS. The sensor in the ABS checks the rotation of the wheels. When the tyre pressure changes, the rolling circumference of the tyre changes ie soft tyre=smaller circumference=faster rotation, harder tyre =larger circumference=slower rotation. It then works out the differences between the wheels and if it falls outwith the ECU's parameters that's when the warning light comes on:thumbs up:
So endeth todays lesson children:idea::moonie:


Thank you professor:lol:

Ferengo
26th May 2009, 12:38 PM
Everyday's a school day :D

GCA3N
26th May 2009, 05:42 PM
Cannot believe this you guys talking about this, then wham driving along today and runflat indicator warning came on. Stopped at a garage 2 minutes away, checked all tyres were at 38psi, so went back in and reset it all ok, see what happens.

AeroJonny
26th May 2009, 06:14 PM
The run flat indicator is linked to the ABS. The sensor in the ABS checks the rotation of the wheels. When the tyre pressure changes, the rolling circumference of the tyre changes ie soft tyre=smaller circumference=faster rotation, harder tyre =larger circumference=slower rotation. It then works out the differences between the wheels and if it falls outwith the ECU's parameters that's when the warning light comes on:thumbs up:
So endeth todays lesson children:idea::moonie:

Don't believe that's true for the R55/6 cap'n :hand:

Big Gordy
27th May 2009, 09:19 AM
Don't have an R56 so :moonie::p
How does it work on the 56 then:confused:

Big Gordy
27th May 2009, 09:22 AM
checked all tyres were at 38psi


Is that not a bit high:eek:
Not having an R56 I don't know but seems a bit high to me......could be wrong AGAIN tho:beer:

GCA3N
27th May 2009, 12:07 PM
Is that not a bit high:eek:
Not having an R56 I don't know but seems a bit high to me......could be wrong AGAIN tho:beer:


Yes i thought that too, i normally have them at 32 on the old cooper, but i presume the garage has set them at that, will need to have a wee check about that

AeroJonny
27th May 2009, 09:45 PM
greig, I think the pressures are just higher on the R56 as I was a bit surprised to be putting so much air into mine. Just checkout the door jam to make sure it's all tickety boo.

I'm pretty sure it's the valvey things with the radio link to the OBC on the R56 gordy

ianking
28th May 2009, 08:25 AM
Valves on the R56 are standard as I had my tyres changed the other day for propers, ditched the run flats.

I thought the R56 measured the pressures via the suspension, i.e if the suspension travels more at one corner then that tyre is low on pressure.

AeroJonny
28th May 2009, 09:39 AM
ok, now i'm just confused...I'll stick with aeroplanes next time ;)

Big Gordy
28th May 2009, 10:34 AM
I thought the R56 measured the pressures via the suspension, i.e if the suspension travels more at one corner then that tyre is low on pressure.

How the heck would that work:eek:
It would have to be able to differentuate between genuine suspension travel and flat tyre movement:frown: If that indeed was how it worked the shocks would be bristling with sensors and as we all know they're not:hand:
Still think my explanation is the best:yes nod: I'm also pretty sure that's how it indeed works:p

Ferengo
28th May 2009, 12:48 PM
"If a tyre loses pressure its rolling radius changes, and this in turn alters the speed of rotation. This alteration is detected and interpreted as a puncture." Quoted direct form the R56 manual, I should have looked it up before posting :blush:.

One other question now. I have a new tyre which is a different make form the stock ones that came on the car. The pressure it says on the tyre is different to that of what it says inside the door on the mini (Mini says 2.2 tyre says 1.7) Which should I inflate the new tyre to?

Big Gordy
28th May 2009, 01:20 PM
"If a tyre loses pressure its rolling radius changes, and this in turn alters the speed of rotation. This alteration is detected and interpreted as a puncture." Quoted direct form the R56 manual, I should have looked it up before posting :blush:.

Wayhay.....I was right:eek:


"One other question now. I have a new tyre which is a different make form the stock ones that came on the car. The pressure it says on the tyre is different to that of what it says inside the door on the mini (Mini says 2.2 tyre says 1.7) Which should I inflate the new tyre to?

If it was me I'd inflate it to what it says inside the mini door:Whistle:Its not generally recognised as good practise to mix makes of tyre that are on the same axis:frown: Its to do with the fact that different makes of tyre have different characteristics so in the extreme case one side of the car could feel different to the other:idea:

Jings another classroom session:thud:

Ferengo
28th May 2009, 05:03 PM
Wayhay.....I was right:eek:



If it was me I'd inflate it to what it says inside the mini door:Whistle:Its not generally recognised as good practise to mix makes of tyre that are on the same axis:frown: Its to do with the fact that different makes of tyre have different characteristics so in the extreme case one side of the car could feel different to the other:idea:

Jings another classroom session:thud:

I had heard that somewhere about mixing tyres, but I really couldn't stand having those michelins for any longer. Once each one goes I'll be going to the pirellis but until then I'll just have to mix 'em. 1 down 3 to go...

GCA3N
28th May 2009, 05:17 PM
Wayhay.....I was right:eek:



If it was me I'd inflate it to what it says inside the mini door:Whistle:Its not generally recognised as good practise to mix makes of tyre that are on the same axis:frown: Its to do with the fact that different makes of tyre have different characteristics so in the extreme case one side of the car could feel different to the other:idea:

Jings another classroom session:thud:


Well done Gordy....:clap::clap::lol: