Disconnecting the battery for that long should have done it........

 

My 96, 5.9L triggered the check engine light a week or so ago.
It was the "too cold for too long" code - it never really warmed up.
I changed the thermostat the other day and now it runs just over 200.
I disconnected the battery for a good 45 minutes, but the check engine light is still on and it's still saying "too cold for too long".

thanks,

 

disconnect the battery and press the brake pedal for 15 to 30 seconds
to reset

 

There you go, doing "IT" again Hey You!!! Answering a question before it's asked. You a freakin' G-E-N-I-U-S!!! So what's your secret?

 

Try setting your PC's clock back five minutes, and see if it happens to you too.... I am WAY curious what that's all about.

 

lol...like the 7th one ive seen.....



my maxima had a code light on, and i tried disconnecting it for 3 hours, and it would pop back on....then i took the battery out, and left it unhooked for 2 days, and then i had no CEL.....so you may need to let it sit longer....

also ive heard when its disconnected, pull the light switch (to on position) this resets the pcm (so ive been told.)

 

Turning the headlights on does not reset the PCM so to speak. It just drains the PCM of any residual power quicker (same as pressing the brake pedal) as mentioned above. Which wipes the memory clean so that it can start fresh. Which is why there is a relearning period.

If the light keeps coming on, it could be the engine coolant temp sensor. A 96 has two, one for the gauge and one that sends a signal to the PCM.

 

I would make sure you actually fixed the problem first. If you can't get rid of the CEL, there's probably a reason.