21:11 Error code Designjet 500

[CPS88]

I replaced the belt on my HP Designjet 500. The belt was truly shredded.  After reinstallation, I got an error code reading 21:10.  It made sense as the service station was really 'gunked up when I examined it.  Not only did it look like the inky examples on-line with black goo at the scraping wheel and spittoon, it also appeared the yellow ink had leaked and made everything a little sticky -even near the motor.  After watching several instruction videos, I removed and cleaned the service station, wiped off the motor, and carefully reinstalled the service station.  Now I am getting a 21:11 Error code 0x301004.  I see some vague information that the service station needs to be adjusted or is not recognized.  I have reinstalled it a couple of times watching the videos ....including the LPS ones.  I cannot figure out what 'adjusted' might mean beyond what I am doing or why it is not being recognized.  The service station, aside from the motor is all plastic. What is there that cannot be recognized?  What is the sensor looking for?  A service call is out of the question on my old plotter so it's up to me to save it.  Any advice? Can you point me to what to adjust? What is likely to 'not be recognized?'  Thank you!

[Repairatrooper]

Plotter this old, if the service station has never been replaced is likely not moving freely and binding causing an error. Try to manually rotate the gears to see if the wiper moves easily.

[CPS88]

I did move the gears and wiper back and fourth manually.  I will take the service station out again and make sure it moves as free as possible.  Is there anything I can do to make the gears on the side easier to turn?  I don't know if there is any lubricant that would be appropriate.  Thank you!