Fuel gauge wiring going thru imobilizer on 98 chim .

[450dream]

Hi all I am pretty new to all this but have been watching and reading forum since buying a 450 16 months ago . I have been having an intermittent issue with my fuel gauge just dropping to zero. I was lucky on one occasion to have it in a failed state and disconnected sender wire and earthed it and ensured tank had a good earth but no change. I am going to get dash reveenered soon so just thought I would ask this question to aid fault finding when dash removed.
Any help or possible other causes appreciated
cheers