veganbutcher
Well-known member
- Joined
- Apr 21, 2012
- Messages
- 71
So I got my car back from the mechanic and noticed the check engine light was on. Tested it and got code 21, coolant temp sensor. The wiring to the coolant temp sensor (located above the thermostat housing) had been cut. I took a picture of the pigtail and all five wires here were disconnected, I figured the yellow/green one must be ground however there are two sets of wires that look identical, both circled in green (one is wrapped in some shrink wrap in the photo but take my word for it).
Are the two sets of identical green wires interchangeable? If not how do I know where they go?
Does anyone know what this sensor is for circled in red? I believe it is a second coolant temp sensor for underneath the thermostat.

Are the two sets of identical green wires interchangeable? If not how do I know where they go?
Does anyone know what this sensor is for circled in red? I believe it is a second coolant temp sensor for underneath the thermostat.

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