with cold engine, the fan temp sensor at the top front of the head has
5,000 ohm resistance. At 80 to 82ºC coolant temp, it is 600 ohms.
One wire is at 5v. (From terminal 8 of the ACC PBU.) The other goes to
ground. via ACC air delivery (whatever that is)
At infinity ohms (plug unhooked,) the fans will come on with the key on.
So if the fans come on at higher resistance, the would seem that the
resistance should get higher as the temp gets warmer. Instead, the
resistance gets lower as the temp gets higher.
I am so far, not convinced that the sensor is good or is bad. It is
still suspect because I don't know what the specs are for its performance.
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