Error 016-370 on Dell Printer 3000cn

I've successfully "downloaded" new firmware for my wife's printer - as I found the info below on another forum, but it still gives the same 016-370 error.  Can anyone help?  She just told me it had called for toner, but I can't imaging dell just giving a cryptic error code if it's out of toner!  Thanks for any help you can give!  Here's the procedure I used (several times):

to reolad broken firmware (dell 3000cn error 016-370):

turn off the printer

1. Connect the printer through USB.
2. hold the enter button (the one in the middle of the circle) with the cancel button simultaneously
3. turn on the printer you will see the following message on the LCD screen
4. " download mode… ready"
5. Start the firmware update from the computer.
6. The LCD will change to "writing…"
7. After about 10 minutes it will prompt you to restart the printer.