how do I check for error codes?

On my Jeep, in order to check for any error codes, I turn the key to the on position 3 times and the error codes, if any, pop up in the display.

Is there a similar way to do this on my f650 diesel?

the jeep has that cool thing w/ chrysler/dodge... you turn the key off-on-off at least 5 times and then you'll read the codes...

what year is the FORD? ~1996 and newer means you got OBDII and that should have a universal plug for a code scanner to hook up to read any codes from most models...

Dependant upon the year, you may or may not have an OBDII connector. That is considered a heavy duty application and may nor of had to comply.