HP 970 problem with the paper path

[Canfree]

HP 970 problem with the paper path

I have 2 HP970 printers.

One is working fine, the other indicates a problem on the paper path.

I have substitute a few components from the good printer but the paper
path lights keeps flashing and the printer only makes noise coming
from the "Service Station Assembly" ( the unit that cleans the
cartridges) when the printer is switched ON and the paper path
flashing light button is pressed

I have replaced the following units:
Power Supply
The master pc board
Service Station Assembly, complete with motor
The feed motor assembly (the one with the plastic disk)

Note:
I have paid particular attention to the installation position of the
small piece of black plastic used to lift the first page (separator
peg lifter)

I have not replaced the Pivot and feed roller ( the unit that feeds
the roller assembly with the "encoder disk")

I know now that I have wasted more then 100 hours of my time but this
became a challenge to my intelligence or stupidity.

Please

John

 

[Tony]

HP 970 problem with the paper path

I have 2 HP970 printers.

One is working fine, the other indicates a problem on the paper path.

I have substitute a few components from the good printer but the paper
path lights keeps flashing and the printer only makes noise coming
from the "Service Station Assembly" ( the unit that cleans the
cartridges) when the printer is switched ON and the paper path
flashing light button is pressed

I have replaced the following units:
Power Supply
The master pc board
Service Station Assembly, complete with motor
The feed motor assembly (the one with the plastic disk)

Note:
I have paid particular attention to the installation position of the
small piece of black plastic used to lift the first page (separator
peg lifter)

I have not replaced the Pivot and feed roller ( the unit that feeds
the roller assembly with the "encoder disk")

I know now that I have wasted more then 100 hours of my time but this
became a challenge to my intelligence or stupidity.

Please

John

John
You have been busy! The time is not wasted if you are having fun!!!!!
If the paper feed light is flashing all of the time then I would suspect that
the paper sensor is the problem, the little flag that operates it may be stuck
in the wrong position or the spring has broken. I think this is buried in the
pivot roller assembly (the one with the big feed rollers) but I have not worked
on one of these for ages. I think the sensor itself may be on the logic board
that you have replaced but the flag is in the main assembly. I'm a bit rusty on
the 900 series but they were in my opinion one of the best that HP have ever
made.
Also the obvious, apologies if you have already done this....Have you swapped
out the control panel, they fail rarely but can cause strange problems.
Duplexer if fitted (there is a paper sensor in the duplexer IIRC). Also it
could be a cable problem, have you swapped out as many of these as possible? As
anyone who has worked on technology knows it is sometimes easy to overlook the
obvious (I've done it heaps of times), hence my suggestions.
Tony

 

[Canfree]

John
You have been busy! The time is not wasted if you are having fun!!!!!
If the paper feed light is flashing all of the time then I would suspect that
the paper sensor is the problem, the little flag that operates it may be stuck
in the wrong position or the spring has broken. I think this is buried in the
pivot roller assembly (the one with the big feed rollers) but I have not worked
on one of these for ages. I think the sensor itself may be on the logic board
that you have replaced but the flag is in the main assembly. I'm a bit rusty on
the 900 series but they were in my opinion one of the best that HP have ever
made.
Also the obvious, apologies if you have already done this....Have you swapped
out the control panel, they fail rarely but can cause strange problems.
Duplexer if fitted (there is a paper sensor in the duplexer IIRC). Also it
could be a cable problem, have you swapped out as many of these as possible? As
anyone who has worked on technology knows it is sometimes easy to overlook the
obvious (I've done it heaps of times), hence my suggestions.
Tony

Tony
Thanks for the information. Just give me time to "digest it".

John