I bought a CX5 Homura 2024 about 10 days ago that had already done 1,300 miles (ex demo car) from Mazda and everything is good. Until today when I put fuel in the car (for the first time).

When I turned the ignition on I believe the gauge was around the halfway mark, which is right as I put around that much fuel in.

Later on the day I had an appointment to professional install a dash cam - Blackview 590x. I am not sure if it was before or after the dash cam installation but since I realised it my fuel gage has been stuck at full! I doubt the dash cam could have messed things up?

I haven’t driven much for it to go down and my estimated miles remaining is updating (currently showing around 340 miles left to empty), which technically is wrong if you only put half a tank in (standard 95 Octane).

Is this normal, as in it takes a while to update or something? Or do I need to take the car to the dealer? It still has Manufacture Warranty.

Thank you.

 

No it's not normal. Fuel gauge do not need any time to update. Take it to the dealer.

 

I see that you are in London so you may not be close to a Mazda Dealership .....
This happens occasionally if the battery is disconnected for some service, or the battery starts to go bad. You may want to double check the batteries health by way of having it load tested. This is prudent with any electrical issues before assuming or performing any action of service. If after and only after you have had the battery load tested, you feel confident as a DIY you can try first to disconnect your negative cable for about 5 minutes and then reconnect. I am sure that your anomalies will correct themselves.
However, if it should continue or feel uncomfortable to do a battery disconnect return to your dealer to have them diagnosis that issue.