Transmission problems in your Mazda Miata will prevent the vehicle from moving. A number of factors affect the reliability of a transmission, including age and the way in which you drive the vehicle. As of 2011, there are no specific factory recall problems associated with the Miata transmission.
The shift lock in automatic Miata transmissions prevent the shifter knob from accidentally moving without your command. If the linkage in the shift lock mechanism breaks, you cannot change gears from "Park" to "Drive" or any other gear.
If your Miata has more than 100,000 miles on the drivetrain, your transmission gears might fail to engage because of wear. As the gears turn past one another, small bits of metal wear off periodically. Excessive metal loss will round the gear sprockets and hinder their ability to turn.
If your automatic transmission reaches critical operating temperatures, the transmission might seize or fail to engage. The transmission contains a torque converter with blades that lock together to transfer power from the motor. If these blades expand, they will break or seize to one another.
