If the sending unit is bad it could depend on RPM. It could take some extra pressure to kill the light. I would check pressure with a gauge before you ride it anymore though. This is similar to why I made oil pressure gauges for our bikes. Wendy washed her bike one time and got the sending unit wet causing the light to stay on. That worried me since I had no idea if it was an electrical problem or the actual low pressure in the engine. Turned out it was the wet unit since once it dried out the light worked fine again but I made a gauge that week so I am sure from now on. I hate idiot lights because usually by the time one comes on the damage is done, with a gauge it is more likely to catch a change in pressure before you lose it all together. Hope your situation is something simple and not low pressure.

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