HELP!
Have 1996 P38 4.6 w/ 120,000 miles. Recently a red "Service Engine Light" appeared on dashboard.

Scanned vehicle w/ OBD-2 and All-Data computer and no codes come up and am unable to disable message.

How to proceed either to locate problem or get rid of warning light?

Am reluctant to bring it to dealer, notorious ripoff. Car exhibits no problems.

Thanks for your assistance.

 

That is the emissions reminder, there will NOT be any codes for it, it is programmed to come on every 60,000 miles or so to let you know it is time to replace your O2 sensors.
If you pop over to discoweb.org -- and look in their tech section there is a "how to reset service reminder" write up.
It is for a DI but I think it also applies to your truck.
It is a simple reset with a paper clip.