Hello Abboud911,
This is Roland corporate tech support and we understand you're looking for a service manual for you LEJ-640FT printer. We would like to help figure out what's going on the printer, so we recommended that you consult with us by completing our online form here: https://www.rolanddga.com/support/product-support-form. We look forward to hearing from you and helping you out!
Take care,
RolandTechnical Support
RolandDGA Corp.
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