First initialize the limit function. This came from a fellow on this site but apparently it's no longer there. Apparently Mr Roland can forget where the print carriage is or something like that and must be limit initialized again. I've had my XC-540 for ~13 years and had to do it only once out of error and once more as a routine.
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It's called LIMIT INITIALIZE. Basically when the machine "loses" itself, it has to be retold where to
start printing, and how wide the printer is (where the cutter down position is).
This is the BASIC procedure for print/cut machines. Refer to the manual or service tech for your
specific machine for any specific procedures.
1.Turn MAIN POWER OFF
2.Remove the sheet/media
3.Remove the side cover to get access to the head carriage
4.Make sure that the cut carriage and print carriage are connected.
5.Turn MAIN POWER ON
6.Press and HOLD the buttons in this order:
LEFT ARROW + UP ARROW + RIGHT ARROW
...then while holding all three buttons down press the POWER BUTTON.
7.You should see the INITIALIZE LIMIT MENU
8.Depending on the model, the caps will lower and the menu will prompt you to Set Capping
Position. Move the head carriage (while still connected to the cut carriage) to the head locked
position.
This position is critical to the success of the operation.
Move the head to the right until you hear the light click where the lock engages. You know that you
are locked when you can no longer move the head to the left. Moving the head past this point (to the
right will unlock it.) This can be a little tricky to find the first time.
9.When you are locked, press enter
10.The machine will display SETTING UP THE LIMIT and unlock the cutting carriage from the print
carriage.
11.Then the machine will display SET CUTTER DOWN POSITION. Physically move the cutting
carriage all the way over to the left until it contacts the left wall, and the sheet cut knife is locked
down. LEAVE THE CUT CARRIAGE THERE.
12.Press Enter and the cut carriage will return to the print carriage.
13.In a few seconds you should see INITIALIZE COMPLETE. If not, try again. Turn off the machine
and turn it back on. You should be good to go.
This simple procedure solves many weird motor errors and other anomalies. A good head strike can
sometime put the machine into a weird place, and this usually solves the problem.
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If you MUST change the scan motor (it is a 'consumable' item with a limited life), you can get one from sign-in-China.com for US $158 + shipping (as of Sept 2020) with greater sensitivity than the original Roland scan motor. It's a piece of cake to change. They also have manuals for the XC-540 via download where you can find instructions on how to change it.
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Clean and lubricate the linear bearing when you clean the print heads. That is the long, shining bar at the back which is about .75" tall. It has a groove on both the top and bottom to clean/lubricate, as well. Don't overdo it.
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The print heads are:
A: Cyan + Magenta
B: Yellow + Black
C: Light Magenta + Light Cyan
There are two sides of each print head, each fed by a different cartridge. It is not unusual to get half a print head not printing and
generally that is a cap to issue. Order up 6 new cap tops from sign-in-China.com for about $32 each. Get 12 new springs and change them, as needed. Don't fool with the cheaper knock-offs. The first time one of those goes bad and you'll wonder if you should have bought the better ones. They don't often need to be changed and the down time and aggravation are not worth doing the cheaper ones. If the heads have gone "too long" and are ruined, you can get new ones from sign-in-China for about $500:
https://www.sign-in-china.com/products/19017/epson_dx4_eco_solvent_printhead.html You can change them yourself but need the manual in order to align/calibrate them. It's tedious and you may not need to do it. Be sure to power down the machine when it says to do so our you'll wind up needing a new printed circuit board for the carriage. I've got the T-Shirt to prove it. Get 12 new dampers if you start changing print heads. Always change 2 dampers with each new print head.
Before you start changing out print heads, do a powerful cleaning or two to see if one of them comes back. Ink is expensive to waste but this is not a waste and is FAR CHEAPER and more convenient than buying new print heads and changing them when you don't need to. Literally, it probably doesn't cost but a few bucks to do a powerful cleaning. If one comes back, you can selectively skip pairs of heads during the cleaning process to save some ink. Check the drain bottle is not full before you start.
Hope this helps.