Engine Coolant Temp Sensor Ohms Curve

malcolm2 · Post by **malcolm2** » 18 Dec 2016, 14:52

Does anyone know where I might find the subject for and '01 S40? I see them all over, but finding the exact one I need has been impossible.

Any help would be appreciated.

I have taken the Temp vs. ohm readings on my sensor, just need to compare them to spec.

One spec I found for what I thought was for an older model 850 Volvo was as follows:
32*F = 7300 ohms
68 = 2800
176 = 300
212 = 150

My readings are as follows:
35 = 5320
72 = 2120
180 = 330
212 = 198

so I never got close to 7300 as stated for the 850 volvo
and never got much below 200 when the 850 model spec was 150

malcolm2 · Post by **malcolm2** » 20 Dec 2016, 07:21

Ok, let me ask another question....

Would a crazy ECT make the fan come on when the air temp is 20*F? the Volvo forum mentions that the t-stat would do that.... How in the world could that happen? There are no electrical connection to the t-stat. The car sat in the garage all night, the engine never started. Key turns to ON, fan comes ON. There is no way the tstat would do that. Hell the fan came on when I was testing the voltage on the ECT connector.... The ECT was removed from the car and so was the tstat....

Looking forward to any feedback..... Hell just say Hi, something!