What I would have done is just tape down the door open sensors.

I think the answer is yes; and suggest you jump start the car. If it starts with a boost, then you know the answer. However, the battery may be weak; how old is it?
Mark

What I would have done is disconnect the battery negative lead. It's under the plastic panel at the base of the rear seat.

If the battery is older than 6yrs I'd just replace it. Seems like once a 6yr old battery goes dead, it's just a matter of time before it'll leave you stranded.

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'64 230SL