Is duplexer installed?

[WyeKnott]

It's been quite awhile since I found HP information about the LaserJet 2420 so here comes two silly questions:

1) How can I tell if DUPLEXER unit is installed in thie printer?

2) If not, is it field-installable?

I just haven't found an HP source that answers these questions.

Thanks...

[Repairatrooper · Accepted solution]

Most of the 2420 units were shipped with duplex hardware installed but no firmware installed to support it. This means you cannot typically physically tell. The only way to know if your printer has enabled duplexing is to go to the troubleshooting menu, select print test. You will see options like paper tray, number of copies and if you have duplex it will offer the option of testing 2 sided printing. I know that this can be enabled through a PJL service file but unless you can find someone with a hacked version you would need to contact HP and tell them that your duplexing stopped working. They may not even offer that type of support for a printer this old.

[WyeKnott]

Thanks. 

My Paper Path Test shows "Duplex: OFF" so I guess that means no hardware.

[Repairatrooper]

No if it shows duplex at all means it will have duplex. You use the up and down arrow to change from no to yes and then press ok this will turn on duplex for the print test.

[WyeKnott]

OK, You've lost me.  When I go to Diagnostics on the printer control panel, I can select Print Paper Path Test and I get a printout that shows like the following:

Source: Tray 1                       Destination: STANDARD TOP BIN

Input Trays                             Output Bins

   Tray 1 Size: ANY SIZE            STANDARD TOP BIN

   Tray 2 Size: LEGAL

   Tray 3 Size: LETTER

.

.

.

Duplex: OFF                              Side 1

That's all she wrote.  There is no clickable option that I can see.