HP CM6040 will not boot up (blank display)

[ConceptZero]

I have just tried to turn on the printer, and it is not booting up fully. It makes a few of the usual start-up noises, but then stops and the screen is blank. I have been through the trouble shooting process and stripped out the formatter and tried printing a test page and this prints a sheet with vertical lines and there is a green led on the CPB Not sure what to do next.... Any help appreciated

[Repairatrooper]

if you can print an engine test with the formatter removed it usually indicates a problem on the formatter. Remove options from the formatter one at a time to see if unit will boot. We had one instance where a failed modem was the problem and the memory used on this model is prone to failure 

[ConceptZero]

Thanks for the reply.

I have now managed to get it to print an engine test with the formatter in place.  I presume that this means that the formatter is not the problem?

[Repairatrooper]

Sorry your OP is not clear.  Do you get any activity on the panel at all? Are you able to access the embedded web server? You may still have a problem with either memory or modem or harddisk. As previously stated, we had plenty of issues with Dimmick memory failure on this model.