21:10 error but service station and bundle board have been replaced

[Mark_Tr]

I have been working on a Designjet T520 (CQ893A).  It keeps displaying 21:10 and wont come on line.

It has had the service station, bundle board, and cables replaced.  No Change in fact fitted 2 service stations and bundle boards thinking DOA.  The printhead and inks have been changed, the encoder strip on the carriage is clean and in good condition.  I can get into service mode and run OOBE and hard resets but this does not clear the error.  I have connected a laptop via USB and managed to get the Designjet utility to run but only by going into support mode and selecting one of the report menus (say 4.1).  The printer does not do anything but the front panel behaves as though it is preparing to print and the Designjet utility will recognise the machine and allows me to check status of consumables.  At this point I can and did update the firmware to  AXP2CN2331AR.  The machine resets, the carriage moves line feed motors initialise and the error comes back.

The only conclusion I have is the main board is faulty.  Any ideas or suggestions would be greatly appreciated.

[Repairatrooper]

That message is a primer pump error. Recheck your connections to make sure you did not leave it unplugged when you changed the service station.

[Mark_Tr]

Hi Repairatrooper thanks for the reply.  I have been off for a few days, and yes the pump is fully connected.

Had discounted the pump because the error for a failed pump is 21.1:00  there are only 2 wires to activate it and no feedback circuitry, hence why discounted.

Is it normal for a pump to do this?

Many Thanks - Mark

[Repairatrooper]

Yes, I read the error wrong and apologize for potentially misleading you.. Question about parts replaced. Were they new Parts or Refurbs or recovered parts from other printers? Swapping some components is not supported, although I see nothing in the service manual to suggest it is not supported.

[Mark_Tr]

Hi Thanks, yes, the parts were new from HP.  In fact I thought that I may have had a DOA so replaced both parts again with new from HP.  That ruled out that problem.

Current line of thinking is that it is a fault with the controller card on the LHS of the machine.  Either it is not sending signals to or receiving feedback from from the bundle board.

If that is the case then the part is not available and might be looking at a new machine, which is very annoying because it has been very well looked after.