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Greetings

I had to install a pre-owned tachometer onto my 2007 s model vehicle, since the previous one's LED display malfunctioned.
After installing it, the device functions well. However, it seems to have disrupted the fuel level indicator on the central speedometer. Currently, I am completely unaware of the quantity of gasoline I possess. Additionally, there are instances when removing the battery results in a decrease in mileage. It is reasonable to assume that this information is recorded in the rev counter unit and originates from the last vehicle it was installed in. Upon disconnecting the battery once again, the car's true mileage is restored. Do you have any insights on the cause of the problem or any suggestions for resolving it?
Thank you.

When I decided to switch to a grey dial for aesthetic reasons, I had the same problem. The PCB board had to be repositioned since it contains different information.

Thank you for your response. Could you perhaps clarify what you mean by "PCB board"? What is this?

In this case, it would be necessary to replace the LCD screen as well.
Extracting the needle is the most challenging aspect, however there are various instructional resources available on Google.