HP DJ T795

[CP-1015]

After permanent error all printheads colleague swapped complete carriage assembly (include PCA and line sensor) without success. Line sensor calibration fails. Carriage Assembly Test: 55:11 No Vpp0 and no Vpp1. Measure up Trailing Cable without finding. Other idee than EE Box? Spezial issue? It's my first T795 I've ever seen. Thanks advance for help.

[Kiran Otter]

Re: HP DJ T795

You probably have a bad or damaged trailing cable; I would replace that first. And if that doesn't do it, then the electronics module WITH the power supply.

In retrospect, always replace the least expensive part in the chain first.

Kiran

PS - Was it a new carriage assembly? Or used?

[CP-1015]

Re: HP DJ T795

[QUOTE=Kiran

PS - Was it a new carriage assembly? Or used?[/QUOTE]


Good question. I'll ask my colleague after his holiday.

[CP-1015]

Re: HP DJ T795

PS - Was it a new carriage assembly? Or used?

It was new. Is there no possibility for measuring?

[Kiran Otter]

Re: HP DJ T795

You mean like checking for voltages at the carriage? You can, but with the nature of the trailing cable constantly being flexed, you may get voltages at one carriage position, and not at another. Plus replacing the trailing cable is pretty simple, and a generic trailing cable is cheap (vs the actual HP part which is stupidly expensive.)

In my experience the electronics module is the most common failure; either the module itself or the power supply, or both together. Then the trailing cable, and last the carriage. But anything's possible. All 3 could fail together.

Kiran

[CP-1015]

Re: HP DJ T795

You mean like checking for voltages at the carriage? You can, but with the nature of the trailing cable constantly being flexed, you may get voltages at one carriage position, and not at another. Plus replacing the trailing cable is pretty simple, and a generic trailing cable is cheap (vs the actual HP part which is stupidly expensive.)

In my experience the electronics module is the most common failure; either the module itself or the power supply, or both together. Then the trailing cable, and last the carriage. But anything's possible. All 3 could fail together.

Kiran

Ok, thank you! But if measuring on the mother board - where trailing cable is connected?

[Kiran Otter]

Re: HP DJ T795

I don't know. In all my years of repairing Designjets, I've never had to determine a problem that way. I wouldn't trust it to supply voltage to something, find a problem, but keep the voltage applied rather than turn it off. Maybe someone else can offer some ideas along those lines.

In some models there are LEDs to indicate voltages. There is one on the carriage I believe on the T-series, that's about the only indication there is.

Kiran

[blackcat4866]

Re: HP DJ T795

You mean like checking for voltages at the carriage? You can, but with the nature of the trailing cable constantly being flexed, you may get voltages at one carriage position, and not at another. ...

Kiran

I suppose that you could clip onto the ribbon contact at each end of the ribbon cable, set you're meter to tone, then repeatedly slide the carriage through it's entire range of movement .. but you're going to spend a lot of time doing this, then not be entirely sure if the cable is good or not.

I have tried this and was not entirely satisfied with the results. =^..^=

[Kiran Otter]

Re: HP DJ T795

For $15, just replace the cable.

Kiran

[CP-1015]

Re: HP DJ T795

Now I swapped trailing cable. Before any justage:
22.0:10
Error-Code 0x10503005
Error: unavailable
File: -threadx-opt/elektra/hal/motors/BPA/elektra/BPSStateMachine.cpp
Line-number: 327

I'd performe IDS/Ink Delivery System.
22.0:10 again. Shell I perform Ink Supplies and Leckage, too?
Thanks advanced.

[Kiran Otter]

Re: HP DJ T795

Check the connectors to the electronics module where the ISS is connected. Look for bent pins. Reseat the connectors. Disconnect the ISS at the ISS and see if the error changes. Was there an ink leak? Are the ISS contacts contaminated with ink? Clean them off.

Kiran

[CP-1015]

Re: HP DJ T795

After reseat some connectors: 08:04. I tried to rewrite new firmware via usb thumb. Since more than 2 hours initialisize 20%.

[Kiran Otter]

Re: HP DJ T795

08:04 is very misleading. It's not a problem with the front panel. In my experience it's the hard drive on the formatter board. But it may also be the formatter itself, or the power supply.

What happened to this printer that it's having so many problems??

Kiran

[CP-1015]

Re: HP DJ T795

Wrong question! Korrect: What I had done that I have to repair this plotter? It's in perfect condition, no ink on connectors.

After interrupt firmware update same error as to begin: "Print heads must be replaced individually"

[blackcat4866]

Re: HP DJ T795

Check the connectors to the electronics module where the ISS is connected. Look for bent pins. Reseat the connectors. Disconnect the ISS at the ISS and see if the error changes. Was there an ink leak? Are the ISS contacts contaminated with ink? Clean them off.

Kiran

I think it was a T2530 ... It kept telling me to re-seat ink cartridges in the right side ISS. Randomly combinations of yellow, magenta, & cyan. I could tell that the enduser had swapped in 3 different yellow ink cartridges, all of which were full. Sometimes swapping in an ink cartridge worked for a while.

I ended up re-seating cables to the right side ISS. It seemed to take even longer than normal to initialize ... then the issue was solved. =^..^=