I have the service engine lite but read no codes. Not sure what to look for, and my old F150 had a reset button to turn off the no code lites.

If your service engine light is lit.....there is a "P" code that is stored.
The code will stay until the PCM sees no issue for a certain amount of time/cycles.
Then the light will go off.

You should be able to read the code(s) with a Generic OBDII code.

If you are not reading any code(s), try using another code reader......you can also go to many local auto part stores and have the code(s) read for free.
Make sure to get the actual numeric code.

It is possible that there is a problem preventing you from reading the codes....like a blown fuse.....connection issue.....etc.