URGENT ONE ! Dodgy Tyre pressure sensor ?

[Yanto]

Guys

Just flipped wheels to my cup shod set. Had them balanced and changed at Elite.

Half mile down the road the red warning light comes on. Stop at garage, check all round and no probs. Reset the gauge. Light comes back on again after half mile

Repeat the reset twice more and it still persists.

Tyres have been stored for 5 months and were stll well inflated prior to change over....

Over active sensor ?? Anyone else experienced ?

Need to leave for Donny in about 1 hour ! Over to you...

Ta

[E46-M3-SMG]

I'd ensure to do the reset again as it'll look like you've done it right until the light comes back.

It's here in post 8

http://www.cslregister.com/forum/showthread.php?t=4740

I'd imagine that's the problem.

[3wheels3]

They can be real pita. Sometimes they take the reset ok other times come back on. Had it once or twice, seems to stay off if dealer resets, weirdos.

[chrisburns]

Or, and you better hope it isn't - it could be one of the two valves that go into the master cylinder.

This happened mine and it is not cheap to fix & a common fault.

[s.mac]

don't panic Ian, it takes a while for the system to accept new wheels/tyres !

[rstoughy]

As above Ian I wouldnt worry about it.
Just reset it prior to going out with the car again and it will probably be fine.
Mine seems to do it every time i change over wheels and can take 3 or 4 resets before it settles down.

[glendog74]

Originally Posted by s.mac

don't panic Ian, it takes a while for the system to accept new wheels/tyres !

+1

Just ignore it.

[NZ_M3]

you need to do the wheel speed sensor reset - drive 30miles+ on open road, put in neutral and pull back both "+" and "-" paddles back for 3 seconds ... it's in the handbook and you have to do this when you swap tyres (does nobody read this??)

Try it, if it keeps coming back, then it's a sensor fault.

[Yanto]

Well got back from Donny and problem has persisted all this time despite resets, with no loss of pressure on checking. Thanks all for input.

Tom, will try your suggestion - in answer to your question, no, I thought blokes were hard wired not to read instructions or manuals ?

[magnust]

Originally Posted by s.mac

don't panic Ian, it takes a while for the system to accept new wheels/tyres !

+1 on that!


But what's this talk about pressure sensors, there are no pressure sensors, it's done in the cars software measuring each wheels rotation speed. Big change in pressure = change in wheel diameter = change of rotation speed compared to the other wheels.

That's why it works whatever wheels you swap to on the car.




PS:
For track days I can really recommend this wireless PMS, it's sooooo handy to keep track of pressure changes when the tyres get hotter:
http://www2.produktinfo.conrad.com/d...e_en_fr_nl.pdf