Truma fire S3002p

[Red Dwarf]

Hi all. i bought this van in December and after following the manual instuctions to the latter it refuses to light ive never seen it lit and dont know much about these fires . i changed the battery and when i press turn and hold the themostat control knob its clicking away nicely ,i then repeatedly press the piezo thing but nothing happens , After learning a few tricks online i take the front cover off and see the piezo isnt conected to anything just earthed to the frame .surely that cant be right? must be a wire missing off that lug on the side ??. This is how it came so im los