Canon i550, i850, and i950.
7/20/2010 by me
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This service manual is divided into the following three parts to provide information necessary to service the i550, i850, and i950.
Part 1: Maintenance
This part describes information necessary for troubleshooting the i550, i850, and i950.
Part 2: Technical Reference
This part provides description of new technologies, etc., used in the i550, i850, and i950.
Part 3: Appendix
This part contains block diagrams, pin layouts, and product specification lists.
download here
http://www.savefile.com/files/1048170