Just thought I'd make a note of this as it hit a clients L7780 printer today.

Problem #1 - Carriage jam error
- Checked carriage area for any jamming issues... found some paper far right (in parking area) which was cleared out. Didn't solve problem.
- Then realised that a small foam pad that sits in one of the cleaning area segments (there's about 3 distinct segments in the cleaning system) was missing. Presumably this has dropped into the workings below.. Can't see it.
- Manually moved the cleaning segments and found small sticking point which was inconsistent so closed lid... Jamming error didn't pop up but gear grinding/sticking sound came through after a few seconds
- Lifted lid again... still no idea what's going on... Will have to locate service manual and disassemble to check the cleaning area workings for problems


Problem #2 - Paper being pulled in part way and then being concertinaed into a jam on left side (paper tray #1)
- Tried fan apart of paper, etc... didn't work
- Eventually looked VERY hard at the pickup wheel and noticed that the central spindle axle (ie: the bit the wheel rotates on) has a bit that looks like it's broken internally and was jutting out.
- Net result the wheel spins but kinks off to one side, directing the paper over to the left and causing the jam.
- Have noticed that the bottom of Tray #1 can be removed after unscrewing a screw so will try that when the unit is brought to the workshop for some TLC. No idea if pin is replaceable or repairable at this point.



So, L7780 is offline for now... Hope this helps someone and if anyone has any ideas... fire away... especially re: problem #1


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Printers: (Canon) MP500/830, MX700, iP4000/4200/4300/4500/5200, iX4000(A3) (Epson) C84/86, D88, CX6600, R285/800/1900 (HP) K550, K850, K5400, L7680