How to Reset HP LaserJet 1500L Drum and Toner

Question

(Note: This also applies to some other laser printers too. If so then please update this thread to indicate the model and any extra instructions.)
The legacy 1500 and 1500L use dumb toner and drum cartages. They have a chip which simply counts the number of pages printed, and when a preset number (as per cartridge size) have been printed, it sends a signal to the printer to replace it. This is ok if you print the average amount of ink per page, but if you print a lot of photos, the cartage will be exhausted before the indicator flashes, and if like the rest of us you print the usual selection of documents etc, then probably about 50 to 25 percent of the toner remains - what a waste!.
Fortunately, (or not) HP kindly provide incorrect instructions how to reset the counter. It's a pity that customer support don’t read their own documentation, or put it in the manual.
Do exactly the following:
1) Turn the printer power switch off.
    Wait 10 seconds for any residual charges to clear.
2) While powered off, press and hold the GO button (right hand)
3) Turn the printer power switch on while continuing to hold the GO button down.
4) After the Go, Ready, and Attention LEDs turn on, continue holding the GO button
    for at least 20 seconds (maybe 30 seconds). During this time, the Attention,
    Ready, and Go LEDs will each eventually turn off.
5) When it seems to have stopped, now release the GO button.
6) The printers LEDs will begin cycling from front to back. After about 15-30 seconds it finishes    
    and everything goes quiet. The printer should now be in the 'ready' state.
7) (The missing instruction) Press the cancel (orange) button.
Send a simple colour document to the printer and it should print out ok, proving it is all ok.
Keep printing until one of the cartages or the fixer toner drum are depleted and printing result is unacceptable.

Answer 1

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