Hi, in my experiance its most likely the wiring to it has a corroded connector, or the display is knackered. Suzuki use basic non tinned looms and crap connectors. The engine should run happily without it, however you'll need to keep a very keen eye on the oil level and tell-tale.
I ran a DT55 without one a few years ago after the Oil level sender unit went down. I hard wired the wiring to Full, binned the sender and sold the multi-display.
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