My Precor M9.23 treadmill stopped working, and after reading the troubleshooting manual and looking at the motor control board, the led indicated that the board is bad. Upon removal of the board, I saw that one of the diodes had failed (blown open). I can't see any indications on the diode to know what to replace it with, but attached is a close-up image of the blown diode, a similar circuit board with the diode intact, and a close-up showing the intact diode in question (small black/gray cylindrical, I believe uni-directional).
2 questions, should I attempt to replace the failed diode, or is it's failure likely the result of some other failed component? I'd rather not replace the entire board if possible, it's ~$300 US.
What can I replace it with? I can't make out what the markings mean. It's roughly 10 mm in length.
I've tried looking for the circuit diagram for this board, or better pictures of the TVS diode, but no luck.