My Drayton Tempest seven reads IO EE?

Your programmer is stuck in programming mode
Turn off the Electrical Supply to the programmer, count to ten, then switch back on, you should be able to reprogramme your settings and all should be well,
If this doesn't wort you may find a small "Reset" button which should be pressed with a pencil or similar
can't remember if the Drayton has this facility though

www.elanar.co.uk
September 2009