Four guys ( a mechanical engineer, an electrical engineer, a chemical engineer, and a computer engineer ) are driving along in a car when it suddenly stops !
"Uhm, reckon it's a mechanical fault", says the mechanical engineer, "we should get out, strip the engine down, then rebuild it, and that should fix it"
"Nah" says the electrical engineer, "I reckon it's a wiring fault and we need to strip all the wiring out of the car, reconstruct the looms, reconnect it all, and that should fix it"
"Well" says the chemical engineer, "I think it's a fuel fault and we need to drain the tank, run a chemical analysis on what comes out, if it's ok we'll reuse it, either that or go and get some fresh stuff, and that should fix it"
All three then turn to the computer engineer and say, "Well what do you think we should do ?"
.... and he replies, "Err, I suggest we just get out and then get in again"