T1300 random 08:04, 08:04.2 and 7904 errors

[fathergratwick]

I have an hp T1300 that randomly comes up with the 08:04 errors... The error log also shows 08:02.2 and 79:04 errors...

I have replaced the hard drive, formatter ,power supply and the interconnect pca board and still the error remains. sometimes I cannot get the printer to even boot without the error and I find in those cases I can remove both rolls of madia and then it will boot as normal.(the error will later come up while it sits idle). I cannot find any damaged wires or anything and am wondering if it could be an ecoder for the media of some sort.

[fathergratwick]

Sorry I failed to mention also replaced the control panel.

[Repairatrooper]

The first step before replacing any hardware should be to print a service plot, verify the status of supplies and replace supplies that are out of warranty. Also ensure that you have the current firmware installed, which I would guess you probably do if you replaced the hard drive, but maybe not.

[fathergratwick]

yes the hard drive was replaced with the formatter. The formatter itself was replaced twice because the first formatter I got was a return that another tech tried in a different machine rendering the hard drive useless. This issue had gone on for months intermittently and all the consumables were swapped out at once as an attempt to repair it by the customer.

Something I have discovered which has me puzzled.. The power switch does not work on the display. Even after replacing the display and power switch.(The customer claims it never worked since new).  However I tested the cable for continuity and if I unplug the power button cable while on the machine tried to power down and then throws the 08:04 error every time you try to power it back up at that point it tries again to power down or sometimes hangs at 1%.  The main pca was replaced with the power supply so the only possible cause I think could be a bad cable? the interconnect pca board makes strange slight squealing noises almost like a modem communicating but the replacement behaved the same way with the cover off.

[fathergratwick]

Ok so I did so further troubleshooting but let me first say the firmware has been updated as well as the consumables replaced. The error will even pop up when the consumables are all removed.

What I did discover is the error comes up when the machine tried to go to sleep or you try to power the machine off from the front power switch. Something other than the actual control panels, interconnect pca, main pca with power supply as well as the formatter with hard drive is causing this. My first thought is a damaged wiring harness but I can find no issues. I have tested the continuity of the power button on the front panels wiring to the interconnect pca. I have followed the wiring through the machine looking for a pinched wire and have found nothing. This is most frustrating.