Diesel Place banner
1 - 14 of 14 Posts

·
Registered
Joined
·
44 Posts
Discussion Starter · #1 ·
So I have not updated my profile so I will lead with my pickup is a 2015 Duramax 3500 4wd (I believe its an LML not positive), I started getting the code P01F0 last spring and after driving with the code for a bit I reset the code with a code reader, apparently the weather had warmed up to never trip the code again all summer. Now that the cold is back so is the code. Everything I have read online states it should be a bad Thermostat, I replaced both thermostats drained and put new coolant in the truck and reset the code again. Again as soon as we got another cool night the code popped up again. After some digging online someone recommended changing the coolant temp sensor. I did this and reset the code and again this morning the code popped up again. I have not actually read the code yet but I'm sure its the same one as the temps are cold again. I do not know what to do next any suggestions would be greatly appreciated. Trying to avoid taking it to the Stealer or a shop, as I try to fix anything I can to save myself a little $. Thanks in advance again.
 

·
Administrator
Joined
·
19,948 Posts
So I have not updated my profile so I will lead with my pickup is a 2015 Duramax 3500 4wd (I believe its an LML not positive), I started getting the code P01F0 last spring and after driving with the code for a bit I reset the code with a code reader, apparently the weather had warmed up to never trip the code again all summer. Now that the cold is back so is the code. Everything I have read online states it should be a bad Thermostat, I replaced both thermostats drained and put new coolant in the truck and reset the code again. Again as soon as we got another cool night the code popped up again. After some digging online someone recommended changing the coolant temp sensor. I did this and reset the code and again this morning the code popped up again. I have not actually read the code yet but I'm sure its the same one as the temps are cold again. I do not know what to do next any suggestions would be greatly appreciated. Trying to avoid taking it to the Stealer or a shop, as I try to fix anything I can to save myself a little $. Thanks in advance again.
When you replaced the thermostats and sensor did you install OEM or aftermarket?
 

·
Registered
Joined
·
3,036 Posts
2011 thru 2016 were LML
2017 - current are L5P

Did you use the 2 different temps of thermostats, and put them in the correct spots?
(a 180F and a 185F, iirc)

Sometimes thermostats fail earlier than expected.

I'd get the code read before doing anything else (some parts supply places will do that, some service receiving bays at dealers will too; both without appointment or cost)
 
  • Like
Reactions: OkDually

·
Registered
Joined
·
44 Posts
Discussion Starter · #4 ·
I did use aftermarket Napa auto parts "premium" stuff not the cheap stuff. I bought the thermostats in a kit and there was an obvious small and larger one, I put them in the corresponding small and larger spots compared to the factory thermostats. Im at work now but when I get off I'll read the code again.
 

·
Registered
Joined
·
44 Posts
Discussion Starter · #5 ·
The other funny thing is that the truck seems to come up to operating temp pretty quick and no change in how the truck runs.
 

·
Administrator
Joined
·
19,948 Posts
I did use aftermarket Napa auto parts "premium" stuff not the cheap stuff. I bought the thermostats in a kit and there was an obvious small and larger one, I put them in the corresponding small and larger spots compared to the factory thermostats. Im at work now but when I get off I'll read the code again.
Aftermarket parts can bring in gremlins on top of other issues you may have. I would replace those thermostats and sensor with OEM parts and see if things change
 

·
Registered
Joined
·
44 Posts
Discussion Starter · #7 ·
I might have to go that rout, I've always had decent luck with aftermarket as long as I purchased from a reputable parts house. I'll read code again. Anyone had issues with fan clutch on these locking up. I haven't checked it yet still at work, but it should free spin when cold correct? At least that's how the older trucks worked.
 

·
Administrator
Joined
·
19,948 Posts
I might have to go that rout, I've always had decent luck with aftermarket as long as I purchased from a reputable parts house. I'll read code again. Anyone had issues with fan clutch on these locking up. I haven't checked it yet still at work, but it should free spin when cold correct? At least that's how the older trucks worked.
Correct it should be free. A locked up fan clutch can also be a culprit
 

·
Registered
Joined
·
44 Posts
Discussion Starter · #9 ·
Well dang, that's not it, fan spins free cold.
 

·
Registered
Joined
·
3,036 Posts
Locked fan is very loud...
 

·
Registered
Joined
·
44 Posts
Discussion Starter · #11 ·
Any chance one of the thermostats is supposed to be installed upside down(spring up) , when I pulled the thermostat housing off the forward thermostat was loose and looked like it flipped from sticking to the housing, but now I'm second guessing myself? I installed both springs down into manifold/motor, the way a thermostat is usually installed.
 

·
Premium Member
Joined
·
18,181 Posts
I'd change the ECT sensor before going further.

Perchance, are you seeing this after using the block heater?
 
  • Like
Reactions: OkDually

·
Registered
Joined
·
44 Posts
Discussion Starter · #13 ·
have not used block heater since last winter
 

·
Registered
Joined
·
44 Posts
Discussion Starter · #14 ·
Crazy turn of events, apparently it is the Def tank heater code now, D21DD. Weird that I fix 1 code and now get a new one. This Def tank heater was warrantied 2 years ago by my dealer and now apparently is causing problems again. Of course now I'm out of my warranty. Anyone have any luck getting something like this warrantied a second time from a dealer. I should have just deleted my DEF years ago but apparently the EPA just shut our whole area down and no one can do it anymore as of recent.
 
1 - 14 of 14 Posts
Top