Well the gauge that is not showing the right level is the one that needs to be attended to like for instance the oil pressure gauge shows like 20 to 30 lbs of pressure at Idle if for some reason the pressure falls below the set pressure the computer turns on the check gauges light! You need to check all the gauges because really and truly a faulty gauge is never the culprit for the light to come on you might have a low engine oil pressure the voltage might be above 14 volts or below it, the water temp might be gettng too high! It's kinda hard to tell what it is without looking at them! Hope this shines a little light on your dilemma! Goodluck!
get someone to check your codes on it it might show something that is wrong ..if your oil pressure at a run time for an hour or a hot engine in park reads lower than 20 psi the pump more than likely needs[ it will have a knocking sound to] replace or you piston rings that would also make the psi to drop ...or if volts show less than 10 than either alternator needs replaced or battery or their is a short which would also drain battery usually...or temp at warmed up engine or hot shows more that 210 temp then either the radiator needs flushed or thermostat replaced or water pump[usually if the pump is bad it will have a little hole on bottom that leaks to tell you its bad] or just low fluid level