RubberDucky

Excellent troubleshooting Wilks42. Hall effect sensors are fairly sensitive devices so the thought that one might be bad or marginal as you said is very likely. I threw a clamp-on amp meter on the negative cable and turned the engine on. I noticed that the current was bouncing from a low of 2.3 amps to as much as 7.5 amps. It made no difference if the HVAC or heated seats were on. I compared it to our other vehicle, a 2007 Acura MDX and it was a steady 6 amps. Since I have already replaced the battery so I'm going to try securing the negative battery cables to the side of the sensor. I tried to look up the part but I'm not coming up with anything. Did the wiring diagram have a part number listed for the HED?