Coping is leaving a lot of black ink dots on the paper.

Odds are that you will need a new OPC drum & drum cleaning blade for the black lines > you may also, need a new primary charge roller & it also, depends if the black lines or marks may be coming from the fixing unit..... There are a lot different cause's.... Good Luck

Ink/toner leak. Clean paper path width soft cloth

ts stop printing and the LED power light green and orange at the center blink, like there is a paper jam.

Try changing the print paper type to something other than plain paper. Use the matte paper setting, or the photo glossy. The printer will lay down more ink at these specialty settings.

replace all color cartridges with black toner
if ink fill your color cartridge with black ink using a refill kit
and just buy a new color cart and keep it asside in a zip lock untill you need color

Does the line appear when you copy from the glass? Or is it Just the document feeder. If it is just throught the doc feeder then you have to clean the **** glass next to the main glass. It only takes a small dot to make a line. Hope this helps. Have a nice day.

this sounds like you have ink on the paper look inside and clean the paper feed rollers with denatured alcahol found at the local hardware store

There is a small strip of glass on the left side directly under the edge of the scanner, About a half an inch wide. It has something on it.
May be very hard to see, use a strong glass cleaner or some alcohol and a regular piece of paper to clean it with.

Not much,in most cases both can be switched, thermal is different, lasers use toner not ink, Premium inkjet paper has better ink asorbition properties with little spread, and paper designed for lasers can cope with the heat applied when it passes via the 180 deg fuser that melts the toner to it. Generally paper used in inkjets and laser is just standard 80gsm paper

Never use labels/transparentcy's designed for inkjets in laser machines they wont cope with the heat,

That would require a very special "white ink" print cartridge for your printer. The regular color ink cartridges won't do this, since they can only make the black paper "black-er" when it prints ink on the paper. You may want to ask the manufacturer (Canon) if they make a special "white ink" cartridge for that printer, or know of someone who does. Your only other option is to make a "negative" print image in Photoshop, or a similar graphics software application, and then PRINT the black ink on white paper... which will then leave everything you want to "print white" as an unprinted area on the white surface of regular paper. (Note: with such heavy printing you would want probably want to use a heavier grade of paper, such as 28# or 60#.) This will use a LOT of ink, but it may be the only way you can accomplish your goal. Hope this helps...