Engine Code 9 : Thermosensor
 

Hi folks.

I've had a CEL light pop in an out on me the last few days, i pulled the code tonight and it's a #9, thermosensor.

Now, i don't have an aftermarket water temp guage, so i don't know what temperature i'm running at. As far as i can tell, i've never seen the stock temp sensor move up once its warm.

What would cause a number 9 CEL to come on intermittantly, without the temp guage moving? If the ECU wasn't seeing temperatures from the thermostat, you'd think it would always be on -- and if i were overheating, you'd think that the coolant temps would rise, rather than throw a CEL.

Any thoughts?

Check the wiring.

Yeah it could be a harness issue.

another thing to do is bench test ,check the resistance on the sensor when it's HOT and when it's COLD.