Check the hoses leading to the heater core from the engine compartment. I had a Nissan that had the same problem. The old owner had by-passed it because it had a leak. Yours could be the same if you are not the first owner.
Hope This Helps.
you shouldn't just follow your coolant hose
If the pump is not circulating coolant insure that the thermostat is not stuck closed. If the thermostat is ok then the pump will have to be replaced.
check the coolant level, or, possible stuck thermostat.
There could be many reasons. Not enough coolant or bad flow, faulty thermostat, low oil. If the coolant freezes then it will overheat. If your car continues to overheat then you should have the coolant flushed and thermostat replaced.
it could be that you've put too much coolant to percentage of water in
You need to check coolant temperature sensor and the water pump.
Coolant at proper level? System air bound and needs to be purged? Water pump not circulating coolant? Defective thermostat? Collapsed radiator hose?
had the same problem with a sibring,took to the garage,they replaced the thermostat and gasket and found a hairline crack in the thermostat housing they replaced the housing and everything was fine then
In the intake manifold, behind the alternator. About one inch to the left of the radiator hose and thermostat.
your thermostat is closed. needs to be replaced. inexpensive part but can save your engine from overheating.
When the thermostat and radiator were replaced, coolant could have dripped into an electrical connector or a sensor could be disconnected or damaged. Check the temperature sensor and crankshaft sensors first.
I just replaced the thermostat and gave the coolant system a flush and replaced the prestone. Seems to have done the job.