Hi, thank you for contacting JustAnswer.com. My name is Russell. I will do my best to provide the right answer to your question.
If the safety key for that model is the magnetic type, that is not put into a slot, but just put up against a spot on the console, then it may be that either the console's magnetic switch is defective/broken, or that the safety key itself was partly demagnetized by having been dropped onto a hard surface (or otherwise subjected to a shock, which can demagnetize magnets), and is no longer strong enough to activate the safety switch and permit operation.
Thinking back, which do you think is the likelier cause of the problem? it would depend upon whether the safety key has been dropped or otherwise shocked, and also whether the console or the whole machine is very old.
In one case, the safety key must be replaced:
And in the other case, the console must be replaced or serviced ( a much more expensive proposition, usually. )
If this answers your question, please rate my answer. A five-star rating would be appreciated!
If you need more info, or have any comments, use Reply To Expert to respond.