Error E5104 in Screen PTR 4300 CTP

[alrasby]

We have this error in our Screen PTR 4300
It says "Transport Unit does not descend"
It seems to be mechanical error.
We tried to resolve this problem but could not and we had another problem E7155 about machine not able to initialize
Looking for help for these problems
Please see attached error screenshots
Thank you all

 

[ChrisZ]

Remove top cover, in what position transport unit is now?
Go to service menu, M55: Path, move it up and down to check is it moving.
Check transport unit springs if not broken.
Check for any mechanical jam.

7155 is Ex155 : Tail clamps are missing during initialization.
Are tail clamps placed on TC bar? If not you must put them there.

 

[alrasby]

Thank you ChrisZ
Much appreciated
We have carried out what you stated
Now error Ex155 has gone

But still we have the the E5104 error "Transport Unit Does Not Descend"
Do you have other suggestions that we can do
Thank you

 

[ChrisZ]

As I wrote:
Remove top cover, in what position transport unit is now?
Go to service menu, M55: Path, move it up and down to check is it moving.
Check transport unit springs if not broken.