Avantra 44 Images Black Page

[avantrageek]

We have a Avantra44 that will image a page and develop black. The black page is exactly the same size as the image sent to the imagesetter. We ran a test page and every where the tones are supposed to be its just a black stripe. Black stripe Clear Black Strip Clear etc. My thought is the laser is not modulating so it it stuck on. We have a spare image setter that we purchased for parts so i can parts available. Any help would be appreciated.

Thanks