Tyre Defect on E39 M5

[EDSEL1]

I bought an E39 M5 last week --- the Tyre Defect notice has recently popped up on the computer read out.

I have checked and pumped up the tyres which were low --- everything was fine for a few miles but the notice has come up again...any ideas?

Apart from that absolutely loving this beast of a car -- it is certainly thirsty though!

[drivin_me_nuts]

EDSEL1 said:

I bought an E39 M5 last week --- the Tyre Defect notice has recently popped up on the computer read out.

I have checked and pumped up the tyres which were low --- everything was fine for a few miles but the notice has come up again...any ideas?

Apart from that absolutely loving this beast of a car -- it is certainly thirsty though!

slow puncture?

[StreetDragster]

With the tyres cold and at the correct pressures you need to reset the tyre pressure monitoring system.
According to the manual-

1) Key to position 2, engine not starting
2) Press and hold the tyre pressure button until "Set Tyre Pressure" is displayed
3) Start the car and drive for 10 mins

Thanks

Matt

[EDSEL1]

Great thanks - will check it out.

[M5Dave]

EDSEL1 said:

I bought an E39 M5 last week --- the Tyre Defect notice has recently popped up on the computer read out.

I have checked and pumped up the tyres which were low --- everything was fine for a few miles but the notice has come up again...any ideas?

Apart from that absolutely loving this beast of a car -- it is certainly thirsty though!

It may just be some kind of glitch in the system.

Mine started doing this, and it happened regularly for a period of about two or three months.

I checked the tyre presures and reset the system several times but it kept doing it.

I then took the car to a BMW specialist who couldn't find any faults. He suggested it may be a failing wheel speed sensor, but said that would probably put the ABS light on as well.

In the end the fault just went away on its own, it hasn't happened now for about a year, and I've no idea what caused it.

[Seesure]

Although I don't have the tyre pressure measuring system (must be pretty rare not to have it on an E39 M5)I still get the "Tyre Defect" message appearing on the dash, however it only occurs once the rear tyres have dipped below 3mm, why? I've no idea, but it might be worth checking the tread on your tyres.

[myke b]

If I recall, the tyre pressure monitoring system doesnt actually monitor the pressure inside the tyre. It measures the time it takes for the wheel to complete a rotation. As the car knows how long a fully inflated tyre of the correct dimensions should take to rotate, if the circumference of the tyre should reduce either by deflation, or by tread wear, the computer sees a reduction in rotation time. This will give a warning to the driver. Only on much newer systems, such as on the new bmw adventure motorbike, do they have actal pressure sensors inside the wheels. This probably explains why the warning comes up below 3mm tread. As for the first post, I suspect a slow puncture.

Hope this helps

[EDSEL1]

I reset the system and it seems to have worked - took for a quick blast last night ---- driving down to le mans for a wedding next friday --- cant wait---

[ArmaghMan]

As others have already stated I'd be fairly sure you have a sensor on the way out.
When it goes it'll most likely take out the ABS and the Traction control.
The good news is the sensors are about £80 and easy to fit.