Originally Posted by Grinder
It's possible to meausure the current flow through the heaters but it's a tricky measurement to set up and the heaters are duty cycled controlled which will mess with your readings.
If both heater circuit codes are set, something common between the two sensors is your problem. The only thing common is the power circuit and the PCM. I agree, it's not likely the PCM but it is possible and this type of scenario is one of the common causes of their uncommon failure....
Are you SURE the fuse is good?
I've made some progress. After installing a new front sensor and getting the same codes, I'm down to one code, P0141, after several read/clear/CEL cycles. Funny how these things work sometime. So it looks like I'll just replace the rear sensor now. The SOB is bent, so it looks like it will be a hassle to remove - anyone have any experience to share?