Run Flat Tyre indicator?

randomer

Can anyone explain to me how the run flat tyre indicators work, and is it rare for them to give a false negative?

I was driving today and the run flat indicator went off. I stopped at a petrol station and all of the tyres were inflated to the correct level. I reset the indicator and about 10 kilometres later the indicator went off again.

I got the wheels balanced yesterday, and have did about 80kms before the indicator first went off. Is it possible that when the wheels were balanced the guy damaged an sensor or something?

Appreciate any information.

shayser

Sorry, don't know how it works. I found on my car that the indicator can delay coming on until quite a while after a change to the wheels/tyres, presumably to learn the new setup? On the other hand, it's then very sensitive, even a slight change of pressure can set it off. I've often reset it two or three times before it becomes obvious which tyre is the problem, usually a slow puncture.

randomer

I have reset it three times now and still cant see which tyre is the problem! Will try again tomorrow. Thanks.

DublinDilbert

The tire pressure monitoring system you have will depend on the vehicle...

There are 2 main types:-
one is based on the ABS encoders which measure the speed of each wheel. As the wheel deflates it will actually spin faster.. They apply long term filtering to the values to filter out the effects of going around corners...

the other type is based on having an RF pressure transmitter, which is typically located on the tire valve stem inside the tire...

Anan1

As DublinDilbert says. If you're still stuck, PM me your number and i'll call you and explain it. :-)

Mr.Diagnostic

Laguna by any chance?

The Laguna, and some others, can be very difficult to reset. The Laguna in particular is troublesome. My solution is to program them out so they no longer give any warnings.

randomer

Thanks for the offer Anan, I may take you up on that.

It is a Z4 Coupe. I have to go into the garage for something else, so I will get them to identify which wheel it is.

Victor_M

The manual in the glove box has instructions on how to reset the pressure monitoring system properly, pressing the button to turn off the indicator is not the correct way, I had the same problem on mine, follow the instructions correctly and the should be calibrated to the current tire pressure.

Any time I get anything done to the tires, balancing or alignments it throws these sensors off.

randomer

The way I reset the indicator was correct.

I brought the car into the garage, and they put it on the diagnostics machine. They found that a steering angle sensor was faulty, so they replaced it (under warranty) and the problem is now resolved.

roonster

hi guys, a few questions about rft looking at buying a 07 320 sport coupe.whats the story with rft? alot of bad reports? where is the cheapest place to get them? up north? do they puncture easy? would be sick if i got a small puncture and had to fork out 300....

Anan1

roonster wrote: »

hi guys, a few questions about rft looking at buying a 07 320 sport coupe.whats the story with rft? alot of bad reports? where is the cheapest place to get them? up north? do they puncture easy? would be sick if i got a small puncture and had to fork out 300....

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