This might be of value for some folks. The new Robo firmware has D5 enabled to do the case lights. However, the documentation is not so straightforward. Here is what has to be done. I verified this error with Allen at Robo. unplug FAN2 (which goes to the useless, stock LEDs.) unplug FAN1 (the fan that cools the robo main board) and plug it into the FAN2 pins. take the PWM signal from FAN1 (which is actually D5, and what is enabled for the PWM for the CASE_LIGHT_PIN in the stock Robo firmware). Hope that helps and saves folks from pulling hair out like I did all week. As an aside, the Fan that cools the Robo control board (now connected to FAN2 label) will only turn on when there is motor movement, and times out after two minutes of no movement.