Hyundai Repair: hondai temp sensor, coolant temperature sensor, engine coolant temperature sensor

Question
2001 sonata temp sensor location?  code says temp sensor low engine checklight went out car ran fine for about 2 weeks. sensor came back on. car idel goes between 1000 rpm and 3500 rpm on own.
thanks

Answer
 SERVICE MANUAL  
 Applies to: Sonata 2001
GROUP
Fuel System MFI Control System



SENSOR CHECKING
Using HI-SCAN
Check item
Data display
Check conditions
Intake air temperature
Test specification

Engine coolant temperature sensor
Sensor temperature
Ignition switch: ON or engine running
When -20°C (-4°F)
-20°C

When 0°C (32°F)
0°C

When 20°C (68°F)
20°C

When 40°C (104°F)
40°C

When 80°C (176°F)
80°C


Using multi-meter
Remove engine coolant temperature sensor from the intake manifold.
With temperature sensing portion of engine coolant temperature sensor immersed in hot engine coolant, check resistance.

Temperature [°C (°F)]
Resistance (kÙ)

0 (32)
5.9

20 (68)
2.5

40 (104)
1.1

80 (176)
0.3


If the resistance deviates from the standard value greatly, replace the sensor.
HARNESS INSPECTION