Service manual for Canon MP980: ftp://mail.racs.co.bw/Canon/From%20Canon%20Training/2h2008%20IJ%20training/Service%20Information/Service%20Manuals/MP980/MP980_ServiceMANUAL_E.pdf
You can copy the link and paste into your browser.
The ftp mail.racs.co.bw server is often down and slow to respond, so have patience, and if you get a time out error, try again later. The server seems to be located in Botswana, maybe it is only online during business hours? Time zone for Botswana = GMT + 2 hours.