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did you know ...,

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Ethicsgradient
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did you know ...,

Post by Ethicsgradient » Mon May 29, 2017 9:49 am

That the run flat warning light lights up if you have a sticky caliper ... I didn't ...I do now . Caliper replaced ...light goes away .

RyanB88
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did you know ...,

Post by RyanB88 » Mon May 29, 2017 9:57 am

Probably confused a sensor somewhere!
Z4 now sold :(

Current - M235i :thumbsup:

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Ethicsgradient
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did you know ...,

Post by Ethicsgradient » Mon May 29, 2017 10:02 am

Certainly did , was not even that bad a stick , light kept coming on I kept checking pressures ..all fine . Eventually jacked up the car and noticed slight resistence when spinning one wheel .Spanners out .... Diagnosed it as corrosion behind the seals causing swelling and stikage .. exchange caliper sourced ..fitted ..two weeks and no light reoccurance .

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Post by buzyg » Mon May 29, 2017 11:22 am

Nice one. :thumbsup: Logged in the memory bank.
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Crazy Harry
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Post by Crazy Harry » Mon May 29, 2017 2:34 pm

That would make sense - doesn't the system monitor wheel rotation speeds and compare them. I've had the light come on driving through surface water on one side of the car - less traction producing a rotation difference. I guess a soft tyre gives the same effect triggering the system so a fractional change in rotational speed from brakes binding would do it - unless of course someone knows different.

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Post by mmm-five » Mon May 29, 2017 2:53 pm

Sticky caliper would create friction, and thus heat.

The heat would transfer to the wheel & tyre, causing the tyre pressure to increase considerably (mine increased had increased by 8psi by the time I stopped to measure it) and thus triggering a TPM message!
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