A bad thermostat is one possibility.
In front of the radiator
Head gasket. Do block test for gases in coolant
on the side of the radiator
i just put in a new radiator and now temperature gauge reads high but their are no leaks
The 1999 Cadillac normal coolant temperature gauge reading should be 180 degrees. A 195 degrees thermostat could be used, causing the temperature gauge to read 195.
The symbol used on the Renault Scenic for a problem with the radiator is a thermometer. There should also be a temperature gauge on the dash that shows the current temperature of the radiator fluid.
Either your oil pressure gauge is reading low , your engine temperature gauge is reading high , or your fuel gauge is reading low so your almost out of gas
Be careful there is a temperature coolant switch mounted next to the thermostat housing. I thought this was the sensor and replaced it by mistake. There is another sensor.
Broken Temp guage
220.
Temperature gauge not moved and the fan's always are working
Is vehicle actually overheating? Could be a bad temperature sending unit or gauge Check temperature with a thermometer If thermostat does not open vehicle will overheat