Just to add to this thread.
My key was getting increasingly stiff and difficult to get out, sticking in the start engine position and not 'pinging' properly when withdrawn, all in all a very mechanical feeling issue. But everything online says to replace the electrical bit and stated the standard part number. So I googled and bought one off ebay for about £8.
Part arrived , with a white body, and I replaced it pretty easily, thankfully one of my hex screwdriver ends was short and small enough to get into the restricted access.
But... when I plugged the electrical connector back on, the radio immediately came on, which seemed strange. but everything mechanically worked the key turned perfectly, the car started etc.. Then I notice that I couldn't lock the car, the radio wouldn't power down and the lights on the dash stayed on even with the key taken out. Something was wrong electrically.
So I re-fitted the original part and checked ebay and ordered up the same part number, but made sure to buy from a seller saying it was for Porsche Boxster, it cost £25, and had a black casing. I fitted it earlier and it's worked perfectly,
So beware... not all part numbers are equal!
ETA, mine's a 2001 Boxster S.
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