I Have An Hp Clj 5550 That Comes Up With A 51.2k Wat Does This Mean

It's a Laser/Scanner error, which you probably already knew, but what could that "K" stand for.

CMYK.

So it's the black laser scanner that's getting an error.

In the 4600 printers I can move the black scanner connector on the DC controller to another socket to verify that the scanner is failing.

Also with regard to the 4600 printers the wires going in to the scanner are harnesses with plugs on them, they can come loose inside the scanner, it's only happened to me once, it was a result of replacing the DC controller.

Here's some more information:

51.XY PRINTER ERROR For help press ? alternates with 51.XY PRINTER ERROR To continue turn off then on

A printer error has occurred.

X Description
1 beam detect error
2 laser error
Y Description
0 no color
K black
C cyan
M magenta
Y yellow

1. Press checkmark button to continue.

2. Turn the printer off and then back on.

3. Reseat the connectors between the laser/scanner (J74 - J77) and DC controller PCB (J1106 - J1109).

4. Replace the defective laser/scanner assembly. Calibrate the printer after replacing the laser/scanner. Use Calibrate now.

5. Replace the DC controller PCB. Calibrate the printer after replacing the DC controller. Use Calibrate now.