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]

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]

[QUOTE=Kiran

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


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

[CP-1015]

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

It was new. Is there no possibility for measuring?

[Kiran Otter]

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]

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]

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]

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]

For $15, just replace the cable.

Kiran

[CP-1015]

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.