When you send JSON  object, then you must convert JSON object to string. For convert JSON  object to string - please use function SON.Stringify

Description:
http://wiki2.iridiummobile.ru/Drivers_API#JSON.Stringify

Example:
device.Send(['PUT,/api\r\n\HTTP/1.1,' + JSON.Stringify(request) + ',\r\n\r\n']);

error body
contains invalid json - this answer from server. Maybe missed char end of line ',\r\n\r\n'.

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