water light come on but levels are full
Never seen a warning light for radiator fluid. You should check your owners manual for the meaning of the icons. I think it's on page 7. You may be looking at an oil warning light. Does it look like a little tea pot? If so, that's oil.
Reelin68 is right. No low coolant warning. If you don't have manual, the icons are on page 27 and 30. And yes, like a tea-pot. If it has wavy lines under it, that low oil quantity. If the same icon without the wavy lines, that's oil pressure. If it looks like water spraying out with broken lines going up and to the side that's windshield washer fluid https://www.manualowl.com/am/Lexus/1996-ES%20300/Manual/6055
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