Hello,

The Mk7.5 (64 plate) Fiesta Titanium-X that we purchased in June of this year has recently thrown up a tyre pressure monitor malfunction.

We bought an extended warranty with the car so I'm not too concerned and it's booked into a Ford main dealer to have this investigated (but not until 20th October)

Does anyone know how the tyre pressure monitoring system works?  From what I understand these don't use TPMS valves that transmit the tyre pressures to the vehicle - my guess it that the car detects the rotational speed of individual wheels and when there's a discrepancy, it suggest an out-of-alignment tyre pressure.

Have though recently replaced the wheels & tyres on the car - using the exact same genuine Ford wheel (17" 8 spoke) bought from a Ford dealer (via eBay) - wheels all had the correct markings so I'm certain they're the genuine article.  I also replace the mixed tyres originally on the car (2 x Continentals + 2 different Chinese brands) with a set of Vredrestien Quatrac Pro All Season tyres.
They tyre pressure monitoring issue didn't occur at the exact same time I changed the wheels (about a couple of weeks later) so I'm thinking that's purely  a coincidence.

At the time I was changing wheels I also took the opportunity to paint the rear drums and the rusted area on the hub of the front disks (see photo)

I just want too check whether changing the wheels & tyres or painting the drums & discs hub could have had any effect on the tyre pressure monitoring system.

Thanks in advance

Does your car have TPMS or the earlier DDS system? My 14 plate has the DDS system which as you say uses the the ABS speed sensors. The TPMS has sensors and transmitters in each tyre valve. I think this system became standard in late 2014. If you changed the wheels and it has TPMS were the valves transferred over.

Aren't TPMS valves rigid?  I've had a couple of BMWs with TPMS valves and there's no flex to them, the ones in the old wheels were just standard rubber valve from what I could see from the outside.

With TPMS valves don't they actually display the tyre pressure for each wheel.  I've not seen that ability in our Fiesta.

Is there anyway to confirm whether the car would have had with DDS or the TPMS system?

Here's a photo of one of the original wheels & tyres - I'm fairly certain that isn't a TPMS valve

3 hours ago, Dazza993 said:

Here's a photo of one of the original wheels & tyres - I'm fairly certain that isn't a TPMS valve

Hard to tell from that photo. Tpms valves on fiesta are rubber like normal tyre valves. Difference is a ridge around the rubber valve on tpms. If you pm me your reg I could check if you have tpms valves or not.