Yes there is. If you have the non-powered seat it is located on the left side of the drivers seat base (door side). If you have the powered seat sit in the seat and look at the base between your legs and the switch will be there.
I do not think the MBS has an emergency start switch. But all is not lost. There are posts in this forum with info on how to install one. Rumor has it that Dynamax is putting them in their Isata 3 series now.
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