HP Laserjet 9040dn no display and engine test fail.

[Biztrend]

I replaced the display and the DC controller and still no help.

[Imagenet_Tech]

Hello, have you tried the print engine test without the formatter? If the engine test works without the formatter board then you are looking at a formatter board issue.

Hope this helps....

[Biztrend]

I have pulled the formatter and the problem still exists, no display and the engine test fails.

[Imagenet_Tech]

Okay, so when you remove the formatter board check the board to see if there is a dimm or firmware dimm, it is possible that the firmware dimm went bad. Best case, all you would need is to order the firmware dimm for the machine. Also, check the formatter to see if there is a hard drive, if so remove the hard drive and try booting up the machine to see if there is any change. If there is a change without the hard drive than the issue is with the hard drive.

[Biztrend]

If the display is blank and the engine test fails with the formatter out, how will removing a dimm from the formatter affect these symptoms?

[davidzuts]

It will not have an effect since your issue may be more than the formatter. Can you give us some history on this printer. The reason I ask is because in order for the engine test to work without the formatter all other components (fuser, pickup assembly, etc have to be working. Do your hear any fans or motor noises when you turn on the printer without the formatter installed. Keep in mind this printer takes a very long time for the fuser to reach operating temp so the printer has to go thru the warmup before you can attempt an engine test since the dc controller will not pickup the paper until the fuser reaches the correct temp. I hope you get my drift. If you did not wait at least 10 minutes to run the engine test without the formatter, then you need to try again. Also make sure you adhere to the instructions below for the engine test:

Media can be picked up from tray 2 or tray 3 if the formatter is installed. If the formatter is removed,
the tray that you do not want to print from must be open. Also, make sure that the print cartridge is
installed in the printer.

[Biztrend]

Yes, all components are installed (fuser, toner, etc.) and it does sound like it is going through the startup sequence. I will turn it on today and check after 15 minutes to see if the fuser heatup is an issue as you suggest. 

[davidzuts]

Also make sure you have the trays set right. I would keep tray 3 open and put paper in tray 2.

[Biztrend]

Finally got the engine test to work after replacing the fuser with the formatter installed. It prints duplex incidently. However the display is still blank so I can't see any messages. I replaced the display also. Tray 2 only installed.

[davidzuts · Accepted solution]

If your display is blank and the engine test works, then the issue is either the formatter, firmware compact flash chip or memory dimms. They are really cheap on ebay.

http://www.ebay.com/itm/Q6477-60002-HP-LaserJet-9040-9050DN-Formatter-Board-w-Firmware-128MB-Memory-...