Myself and a Cpl Leccie trying to find out why our F3 Flaps and Slats kept operating out of synch depending on which Hyd systems you used and when both on together, this had been worked on for some days. Despite nearly causing a fire at 2 in the morning, we finally tracked it down to one of the solenoids on the front of the HLWSCU, found one in stock, changed it by the time day shift came in it was a serviceable jet. Only problem was we where then asked to write up our fault diagnosis for the AP.
Same team asked to look into a CSAS BITE failure immediately on pressing button, again we started at the front and found that there is a configuration loop in the circuit (single cable) which makes sure the wings are forward, Flaps/Slats are up, Airbrakes closed and Taileron actuators around neutral. started continuity checking and found the culprit at the base of the fin, the cable had snapped at the terminal post.
I seem to remember Tornado crew ins when the Avionics guys get called out to sort some problem out, and like others have said it usually turns out to be finger trouble, one did not realise that if the Master Computer switch was OFF, not much worked.
My biggest laugh was on 5 sqd F3's, 5 had gone to the states and I stayed on base, the deputy Sqd Commander came back with a learner with a Flap/Slat/Wing Sweep snag. Plugged in head set, glorious sunny day by the way, and asked what the problem was, it appeared that when he selected the Flaps/Slats Down with the normal lever the wings would not sweep, conversely when he swept the wings the Flaps/Slats did not move. When requested by me he demonstrated all the problems he had and at my request did it over and over again, when asked to go through the sequence with the Manoeuvre Switch he said oh look its working now, then the deputy Sqd Commander had one of those lightbulb moments, followed by ok PE I get the message, my response was I would like to help the other person to learn how the aircraft works, unfortunately the next response I will not repeat. Back in the HAS when they climbed out the young aircrew person asked the Deputy SQd Commander what was going on, he just hit on the back of the head and said I will speak to you in private, to me he just said smart arse and walked off.