Oil light comes on when engine starts cold

The oil light on my 2005 Chryler Town & Country comes on when started when it is cold outside. It stays on until I turn the key off and restart, then it goes out and does not come back on. My mechanic cannot find anything wrong. This only happens in cold weather, not in the summer. Any ideas?

Has your mechanic witnessed this???

Since it goes out once you turn the engine off then back on…I’m guessing a bad oil sending unit.

I don’t think he has seen it because it happens when I go to take it to him. I would have to leave it there and have him see it happen, but he suspects a computer error.

What is an oil sending unit?

I agree with Mike that it’s probably a bad oil sending unit. I included a picture of an oil sending unit for a 2005 Chrysler Town & Country with a 3.8 engine. It’s basically just a switch that senses oil pressure.

Is that something that is important to replace, or does it not matter? Can I replace it, or it is complicated?

I’d replace it so you it can alert you of legitimate problems. Not sure on your car but usually it just unbolts and the new one bolts back in.

Thanks for your help - I will take care of this and see if it cures the problem

Thanks for your help - I will take care of this and see if it cures the problem

One other question - if the oil sending unit is bad, why does it only malfunction in cold weather?

It is common for many electrical malfunctions to be temperature dependent. Metal expands and contracts according to temperature, opening and closing gaps and contacts.