coolant temp sensor location

2016 BMW 328
101,000 MILES • 4 CYL • TURBO • 2WD • AUTOMATIC
Avatar
BHAMDOC1973
  • MEMBER
  • 2,008 POSTS
I hear either there are 2 of them one on front and one on the back of the engine or am missing something changed the front one cause fan comes on and had a p0118, but its a stubborn code that won't go away and keeps saying permanent, I saw a video of someone replacing one in the back of engine, is there one back there?
Sep 21, 2025 at 9:28 AM
Advertisement
Avatar
STEVE W.
  • CERTIFIED EXPERT
  • 15,113 POSTS
Permanent codes will stick around for a set number of drive cycles after the PCM detects that the fault was repaired. They cannot be erased with a scan tool. If you don't have a pending or current code for the same thing then it just needs the drive cycles to remove it from the system. The factory ISTA system can delete them earlier but I don't know of any other unit that does. You will run across them in many of the newer vehicles as well. Although they claim it is to prevent people from simply erasing codes I think it is more of a tattletale system, showing that you didn't take the vehicle to a dealer or "authorized" shop.
OH, there is only the single sensor on that engine.
Sep 21, 2025 at 11:32 AM
Avatar
BHAMDOC1973
  • MEMBER
  • 2,008 POSTS
Oh i see. But i never failed to erase codes like this with my autel, this is a first for me
Sep 21, 2025 at 12:10 PM
Advertisement
Avatar
STEVE W.
  • CERTIFIED EXPERT
  • 15,113 POSTS
It's a common problem in a lot of the Euro vehicles. They won't let the aftermarket tools erase the permanent codes.
Sep 21, 2025 at 9:53 PM