When we first received the 333s, they were a total step change from what we had experienced before and a lot of the older drivers, especially those who had started on steam and were approaching the end of their careers, found it very difficult to get to grips with things like computer diagnostics. Added to that, there were a lot of problems with the software in the early days, which the Siemens engineers at Neville Hill put down to the shaking that the units received on the less-than-perfect permanent way on parts of the Airedale and Wharfedale lines. You would be tramming along quite nicely for four or five trips and then, suddenly, the Train Management System VDU would start bleeping and a spurious fault would be flashing on the screen....usually when you were braking on the approach to a station stop. A few seconds later, another fault would show and before you knew it, every fault in the book was flashing and bleeping. If you were unlucky, the brake would be unceremoniously dumped. If you were lucky, it would let you get into the station. The procedure then was to phone/radio the signaller, put down the pan, switch-off the unit, wait 30 seconds, switch the unit back on again, put the pan back up again, contact the signaller again and away you go.....nine times out of ten. Just like re-booting a computer, which was effectively what it was. If it didn't clear the 'faults, then you had big problems! You also had to inform the conductor of course, because sometimes when you switched-off the unit the doors closed automatically and during the hours of darkness, the saloon lights went off. All this took time of course and caused delay.