Laser Unit HP CM6040

[MWALA]

After i cleaned the laser unit after very bad copies when using the document platen glass an error code 52.00 appeared, followed by 51.21 all pointing to the laser unit. All I did was cleaning. How can i got this right

[HP:guy]

If the cyan or black component
tests showed a startup failure,
reconnect the connectors of the
cyan/black scanner motor (J1702)
and the DC controller PCA (J129).

[Wild Bill]

If the printer was working before you touched it, always Back track; Did you clean the mirror inside?
Go back to everything you touched; you may have dislodged something a connector or left a smudge on a mirror or the motor;

You really should get a manual if you don't have one already; www.JustManuals.com

Perform the laser scanner component tests in the Troubleshooting menu.