TPMS not allowing me to reset

[Conquistador]

I have searched for this problem, but can't find the answer.

I hit an almighty pothole recently and the tyre went soft - I knew immediately it was yet another cracked rim (E89, style 296 wheels). TPMS light came on very shortly after. I got it welded as soon as possible and it now drives fine.

The pressures are spot on and it drives fine, tyres have all been changed to Contisport 7s non-run flats but when trying to reset the tyres through the indicator stalk, the little tick box doesn't come up.

I'm wondering if the pothole also took out the valve sensor on that wheel, as it functioned as it should before that.

Anybody had a similar experience or have any suggestions?

 

[Scooba_Steve]

have any suggestions?

Just buy a pre-coded cheapo replacement. I got a set of 4 off eBay or aliexpress for about £20 with valves and they've been fine. Even if they only last 2 years it's still much cheaper than BMW.

 

[Nictrix]

I assume your car does have tpms valves on the wheels?
You haven't said what year or model your car is.

 

[Conquistador]

I assume your car does have tpms valves on the wheels?
You haven't said what year or model your car is.

I mean, that's a very good question. I am presuming it does, because the system has functioned in the past as it should. When the tyres have been off the rims in the past though, I don't recall noticing a big chunky valve on the inside of the rim. You've got me doubting myself now.

Car is a 2010 sdrive 35i.

 

[Nictrix]

It shouldn't have tpms valves in the wheels then.
That system was introduced on later cars.

 

[Conquistador]

Forgive me for being dense here, but if it doesn't have TPMS, will replacing all 4 wheel valves with new TPMS valves just have the same fault?

 

[Pondrew]

Forgive me for being dense here, but if it doesn't have TPMS, will replacing all 4 wheel valves with new TPMS valves just have the same fault?

If the car doesn't have the TPMS system using wheel sensors, then putting wheel sensors in will not do anything as there is nothing to pick up the transmitters.

An easy way to tell if you have wheel sensors is look at the valve stems. If they are flexible and have no visible 'nut' they are standard and the tyre monitoring is done by the ABS sensors. If they are solid (usually aluminium) and have a 'nut' they are sensors.

 

[Conquistador]

They definitely have flexible stems, I remember bending them to clean around them when doing the wheels.

Which I guess leads me back to my question of why is the TPMS not allowing me to reset? Would pulling fuse 27 fix it I wonder?

 

[Mr Tidy]

If your car doesn't use the valves for the TPMS it will have wheel speed sensors, so maybe one of those has been disturbed when you hit the pothole.

 

[B21]

If your car doesn't use the valves for the TPMS it will have wheel speed sensors, so maybe one of those has been disturbed when you hit the pothole.

Man speaks good idea.. :tumbleweed:

 

[enuff_zed]

If your car doesn't use the valves for the TPMS it will have wheel speed sensors, so maybe one of those has been disturbed when you hit the pothole.

Man speaks good idea.. :tumbleweed:

If it's the same system as the E85 then I would expect a decent code reader to tell you which, if any, of the ABS sensors is not working.

 

[Conquistador]

The TPMS light came up shortly after the pothole incident, and hasn't allowed me to reset it since, despite the correct tyre pressures and still being able to drive for a few hours each time before having to reinflate (I was in Scotland at the time, and needed to drive back down to London!). After I got the rim welded, I took the opportunity to change the front tyres from 225 35 19 to 225 40 19 to give a tiny bit more sidewall.

Bimmerlink brings up the following errors. Have I upset the car by increasing the circumference of the tyre slightly perhaps?? Buying some tyres of the original size only to find I still have the same fault of not being able to reset the TPMS is going to be an expensive way of ruling that out!

Edit to add: a few months ago I changed just the rear tyres and went up by 5% on the sidewall with no TPMS error.