How to Darken Print Output on Laser Jet 600 (M601)

[Bobwolf1]

I have a relatively older HP Laser Jet 600 Model M601 which is printing too light in spite of having a new full toner cartridge. Two questions: First, how do I make the print output darker? Secondly, when I try to get to the maintenance options on the control panel, I get a message “Options Conflict Invalid User Name, Password or Access Code. To the best of my knowledge, I’ve never put in a user name, password, or access code in this machine. However, over the years I had outside service contracts and I suppose they could have put in some in the service process. Except for the light print, the machine is still working fine. Any help would be greatly appreciated!

[Repairatrooper · Accepted solution]

Here is a document that shows all the menu options https://support.hp.com/us-en/document/c03032403

You can try increasing the toner density. 

In terms of clearing a password, see 1:40 of the attached video on entering the preboot menu, ignore the rest of the video. Once in the administrator menu you want to perform a partial clean.

[Bobwolf1]

Thanks so much for your quick and helpful response!

I couldn't find the attached video you referred to for instructions on entering the reboot menu and performing a "partial clean".

I'm new at this site and may have failed to recognize the link.

Thanks again for your help! 

[Bobwolf1]

Greetings again, Repairatrooper.

Please disregard the last reply. I was able to resolve my problem with your excellent instruction

Thanks again for your amazing help!

Have a great day!!

Bobwolf1