ECT( Engine Coolant Temperature) Sensor

ECT ( Engine Coolant Temperature )

Manufacture's Specification;
Temperature               Resistance
     (deg C)                      ( ohms)
       - 10                      7000 - 12000
         20                      2000 - 3000
         50                        700 - 1000
         80                        200 -   400
         85+                   Lees than 200
Measuring the resistance ;

I had take those pictures in diffrent temperature multimeter reading  ohms

Water Temperature	Resistance
19 deg c	2.66 K ohms
30 deg c	1.68 K ohms
36 deg c	1.34 K ohms
42 deg c	1.09 K ohms
50 deg c	870 ohms
55 deg c	670 ohms
60 deg c	600 ohms
70 deg c	435 ohms
80 deg c	300 ohms
90 deg c	250 ohms

In the chart up i had record the ohms reading in different temperature
 does the sensor meet manufactuter spec.. , what type  sensors , internal operation?

The inside of ECT sensor is found a thermistor , which is an electronic temperature sensitive variable - resistor. The ECT  ( thermistor) is an negative temperature coifficent sensor , this mean that is tmperture goes up resistance and voltage goes down or visversa.
The ECT works by changing it's internal resistance according to coolant temperature and therefore also changing the voltage drop according it .
The ECT signal determine by two diffrent pull up resistor inside the ECM. A high (3.60 K ohms) and low ( 345 ohms) impediance circuit is provided internally by ECM for the volts refrence.
A low coolant temperature the ECM uses of the pull up ( 3.60 K ohms) as temperature increase and over certian temperature value around 120 deg f . The ECM switch 5 v refrence internally to other pull up resistance 345 ohms.