Alright Northerners, is P1281 normal?

[mudhog55]

For the last week our temperature has been dropping below 40 degrees F at night. My engine light came on, so code reader shows P1281 engine temperature below operating temperature or something like that. I'm still driving it, and it seems to be running normal. 2023 I installed all new radiator, water pump, thermostat, hoses etc. Is this something normal that pops up when it gets cold or something I should be concerned about. I did not clear the code but waiting to see if it clears itself. Temp gauge seems to work but it does not get to the middle reading, heater blows hot air. 2003 4.0 standard. 110,000 miles.

 

[jjvw]

What temp thermostat did you put in?

A CEL is never normal.

 

[macleanflood]

What's the computer say the temperature is?

I'd probably be using my Bluetooth dongle and Torque Lite to monitor temperatures.

Have you tried the cardboard in front of the radiator trick?

-Mac

 

[jjvw]

....

Have you tried the cardboard in front of the radiator trick?

-Mac

He should not need cardboard at 40°F. That is not cold.

 

[mudhog55]

What temp thermostat did you put in?

A CEL is never normal.

I do not remember what setting it was but everything I purchased was after reading peoples suggestions on this sight. It was not the aftermarket "F" brand but it did fit the descriptions recommended. That is the first thing i will change if code does not clear.

 

[mudhog55]

I only have a little handheld code reader so I don't think it can give me actual temperature readings. Where is the sensor located maybe I can expect it to see if it is working.

 

[Gilaguy23]

Its 7 degrees here this am. Last year we had -10 for a week or so and have never seen a "its cold CEL". Theres always the living room if the wifey is OK with that.

 

[tr21triton]

your temp should be on the 1 of 210 or really close. if not odds are you have the wrong or a bad thermostat. a bad temp sensor is also possible. what was it reading before you changed it out ?

 

[macleanflood]

He should not need cardboard at 40°F. That is not cold.

My mind saw -40°F when I read the post. Oops.

-Mac

 

[James9100]

Definitely not normal, 40°F isn’t even cold yet. Our winter average is about 15°F to -5°F and I’ve never got that code.
About where is the needle sitting at the temp gauge once it’s warm? Is it actually below operating according to the gauge?
If not I’d just clear the code and see if it comes back.

 

[g.hayduke]

We just got back from Big Bend, TX. It was below freezing a couple of those days. Texas has been super unusually cold. Yes, 40f isn't cold for most of the US in January but for some places in TX. could be the coldest ever seen.

That said sounds like a wrong or bad thermostat, as suggested.

 

[lBasket]

We just got back from Big Bend, TX. It was below freezing a couple of those days. Texas has been super unusually cold. Yes, 40f isn't cold for most of the US in January but for some places in TX. could be the coldest ever seen.

That's still T-shirt weather if the suns out!!!!

 

[mudhog55]

Update. I changed thermostat out. The existing one was 195f and it was seated right and was not stuck open. I changed it and disconnected battery to clear code. I drove it just a few miles and so far no CEL and temp. gauge seams normal. I cleaned the sensor up at the same time. BTW it was 65f Saturday when i did this, and this morning it was 31. Thanks for replies and tips.

 

[tnjeepguy]

Like that blue TJ and wheels. Nice. Glad you got it fixed.