Ford Explorer Coolant

My Service Engine Soon light came on in my 2005 explorer. I took it to Advance Auto Parts & they plugged it up to the reader and it said something about “coolant.” The guy who did it was not helpful at all and could not tell me anymore, other than I needed to take it to a shop. Any thoughts on what this could mean?

First, check your coolant level.

Second, go to a different auto parts store with a friendlier employee, get the exact code, and post it here.

The code may have indicated that coolant didn’t come up to the proper temperature over the time the engine was operated. This code is usually caused from a thermostat that is defective/stuck open.


Thank you so much your help! I will get the exact code tomorrow and post it here. Thanks again!

Has “Service Engine Soon” Light Been Turned Off ?

The light can either be turned off with the tool that reads the codes or it may go out all by itself if the car’s computer system goes through a number of cycles without more incidents of this problem. It could take a couple of days.

If you’re just getting the light and are experiencing no differences in the vehicle’s operation (rough idling, rough running, etcetera) then I personally wouldn’t rush into a repair.

I’d turn the light off or see if it goes off and then wait and see if it comes back. Sometimes it will (problem continues) and sometimes it won’t (no problem detected).

However, a thermostat replacement probably isn’t and expensive repair and if it’s been a while since you’ve had the engine’s coolant replace, it might not be a bad time to do both together.

Are your heater and defroster working well ?
Have you noticed it taking a long time to get heat ?
Is it running well ?


‘‘something’’ about coolant ?
What exactly ?
That’s what the code will tell us BUT…
Also, repeat the words verbatum even if you don’t know what they may mean at this time and we’ll tell you more.

This strategy is something I’m trying to impart to my second round of kids.
Whether it be the teacher, doctor, or whomever…if they tell you something you don’t quite understand, don’t write it off as ‘‘whatever’’ or ‘‘something like…’’

  • Repeat exectly the words they used .
    Then we can take it from there.
    ( I tell them to act like a tape recorder…which is another foreign concept to these digital kids these days. )

Also a method I use at the doctor’s office. I tell them to get technical with me as I write it all down.
Terms I don’t understand at the time I’ll research later.