bassman212

I have a 2006 with 5.4 engine. I purchased with 97,000 miles. My first problem was a check gauges light and the transmission temperature gauge wasn't working. Since it was running rough and had never had the spark plugs changed, I decided that was the most important. After changing the spark plugs, I got the P 1289 check engine light and the air conditioner compressor won't turn on. A scan gauge shows that the engine temperature stays at 53 degrees, but the vehicle temperature still shows normal.
My research tells me that the AC doesn't work with that engine code and since I got the code after I changed the spark plugs, that I created a loose connection or break in the wires going to the head sensor. My question is there a plug in wires going to the sensor and where is it located and how are the wires routed? Also, would the transmission temperature not working be related?
Thanks for any help.