Hi,

My engine light came on indicating Engine Coolant Temperature Sensor is tripped. I have checked the resistance of the sensor but am not sure I did it correctly. There are two pins off the sensor when I checked the resistance between the pins (engine warm), it was approx 500 ohms. But the Hayes manual said that the resitance should be checked against the pin (didn't say which pin) and an engine ground. When I checked either pin with ground (negative battery terminal), I didn't get any reading? Did I do something wrong or is the sensor shot? Help

Chris...

 

I'm a complete novice with respect to testing stuff. I applaud your efforts to test, but in case you don't know, you can find an ECTS on the internet for ~$20 and for $40 at your local auto parts store.

 

it was under $30 at Advance Auto....you don't even have to drain any coolant...takes 30 minutes tops.

 

but it's not needed if your sensor is still good. when you look into the sensor you will see 2 pins. put 1 probe on one of the pins and put the other probe on the other pin (both within the sensor). your ohmmeter should register around 2.15 kohms when cold and should register around .25-.30 kohms when fully warmed up. the reason i say test it is because i had the same problem but my sensor was good but the connection had corroded a little. i cleaned the pins and put some conductive grease (available at Fry's) onto the connections. good luck!

 

either way it wouldnt hurt to replace the sensor, i got a new for 27 bucks at the dealer

 

apbrian112, thanks for your input.

I'll try to test it again when its cold. My reading of 0.5 Kohms seems high with a warmed up engine. I did spray some contact cleaner on the sensor pins and the harness clip and reset the codes. Waiting for them to come back (2 days now)!

Thanks again.

PS. the local dealer sells these sensors for about $40CDN. But I don't wish to replace parts that can be fixed or cleaned. Hence the reason for visiting this site for good information.

 

http://www.autozone.com/servlet/UiBr...3d801f4731.jsp