Morning 

I have just purchased a 2017 Focus Ecoboost, it has come up with the service engine now warning, we have now serviced it, also checked the fault codes which is came up with the Catalyst fault, we changed the o2 sensor reset the code and the fault code hasnt come back, car drives fine, but the service engine now warning is still on, we have tried the both pedals down reset and it comes up as complete but the wanring still stays on, any ideas? 

Also, it comes up the tyre presssure sensor not being read, is this a fairly simple change the sensor job done? 

I didnt pay a lot of money for the car so expected some niggles, just wondering if anyone can give any advice? 

Thanks 

Stef 

Good morning Stefanie and welcome to the Ford Owners Club.

Are you using Forscan ?

If not then it would be best to do so (it's free). You can download it from here:-  https://forscan.org/download.html

You will need a good quality ELM327 lead to connect to your laptop.

Most like to use the one from TunnelRat Electronics:- https://tunnelrat-electronics.fwscart.com/USB_Modified_with_switch_ELM327/p4541936_17045457.aspx

Check with Forscan and it may give more information as to why you are getting the 'Service Now' warning. You can try and clear it with Forscan.

The tyre pressure monitor problem maybe that the wrong (or no) sensors have been fitted when tyres have been replaced. Again a check with Forscan will tell you which wheel(s) are causing the problem and why.