Reading the service bulletin I linked, I noticed that the diagnostic flowchart mentions “lighting position”, which to my best guess refers to the headlight levelers. I have oem levelers, but powered through the headlights fuse and no signal to the ecu. Based on that, I disconnected the whole thing and so far all I’m getting are fuel cuts without the Temp needle jumping to High, and the only code that pops up is the C0047.
Everywhere I look, that code means a bad ABS module. I’ll be ordering one soon to test and update accordingly.