I have 75,000 miles on my 2012 Expedition EL and my check engine light came on the other day. I busted out my handy dandy code read I am getting a heater circuit malfunction from all four sensors. I find it hard to believe that all 4 sensors died at once and assume there has to be a relay/fuse that has something to do with the HEGO system. I looked in the owner's manual, but I can't find anything related in the fuse/relay diagrams/tables.

Does anyone know of a fuse or a relay tied to the HEGO system? Do they just call it something different in the manual? Thanks in advance for any help.

 

I would take it in to a mechanic you trust. Sensor fault don't mean the sensor is bad. Replacing sensors doesn't often cure anything.