I am trying to identify a faulty transistor on a BPSX D1 WBO Controller.
The transistor controls the 12v for the heater on a 5 wire Bosch WO2 sensor.
I am hoping someone have the same unit and could take a photo of the board.

 

Have you checked if there are any markings left on the transistor itself? Sometimes even a partial code can help identify the replacement part. If someone has the same controller, a clear photo of the board would definitely make it easier to compare the components and trace the heater circuit.

 

board manual should explain voltage, connections (type of load) etc. alternatively trace how it connects to the rest of the circuit. then you may not have the part number but enough info to select substitute.

 

There are several photos of this board on car modding forums, in particular the Miata Turbo, however none shows the markings on the transistor well enough to read.