My Smoothieboard has been a rock star since day one. I think we are on day 365+. Until last week I've been using a standard computer fan for PLA cooling controlled by the mosfet at pin 2.6. This has worked without issue. However, the performance of those types of fans are not very good so I decided to switch to a ducted fan. This was working great until yesterday. The fan will not turn off. I have tried re-setting the board and it just will not turn off. The LED for that pin is on and the fan is powered up. I have tried M107 and M106 S0 to no avail.
When a mosfet fails, does it fail in a closed state? Will it damage the board if I leave this as is and just switch the fan to a different pin?