ODD feeding rollers do not activate.

I am a tech at a local ubreakifix, and I am having issues with a customers system.

When attempting to insert disk the rollers will not activate.

I have replaces the motor that trips when butterfly mechanism when open enough to activate switches with no success.

Swapped full sensor unit with another ODD and no result from that either.

I know that the daughter boards on these guys are married to the boards that they were issued with but unsure of location on the slim model (maybe integrated into sensor unit?)

If anyone else has discovered a solution please share! Thanks!