Mazda Miata Auto To Manual Swap Guide (NB)

Today we're covering the basics of an automatic to manual transmission conversion for a 1999 Mazda Miata. Below is a full description of the wiring that needs to be completed that will allow full functionality of all systems.

Neutral Safety Switch
Find the large connector that used to hook to the side of the auto tranny. There are two heavy gauge wires - Black with Blue Stripe and Black with Red Stripe. These can simply be spliced together and the car will start. You can also tie these into the two small single wire white plugs coming off the top of the tranny. That will require the car to be in neutral to start. There is no polarity to worry about, as it is just a switch.

Reverse Lights
The other connector coming off the manual tranny that has two conductors and close to the neutral safety switch is the reverse lights switch.
On the same large auto connector you found the neutral wires - look for the Red with Yellow and Black with Yellow wires. Splice these together with the two wires from the small connector you just cut off. Again, polarity is not an issue.

Speed Sensor
Connect the speed sensor on the transmission to the Yellow and Orange wires on the car side. (one of the dangling connectors has yellow and orange wires, pretty easy to locate) Unclear if polarity matters.

Speedometer
Splice together 2 pairs of wires that were going into the Automatic Transmission ECU with the following colors.
Connect Black/White to Orange
Connect Yellow to Black/Blue (Ground)

Cruise Control
Cut the purple wire going into the Cruise Control ECU (driver side under dash)