joaoxx
New Member
I have run into this incredibly frustrating issue on 2 or 3 different Mimaki UCJV300-160s now, and I cannot seem to nail down a definitive fix. Sometimes the issue just magically disappears, but on this current machine, it’s hitting hard.
It always starts with Positive Pressure errors, which quickly cascade into or in combination with a persistent Ink Overflow error. On this latest machine (configured as CMYKLmLcWW), it is strictly throwing the Overflow error on Light Cyan now (It also had a Positive P. Notenough but after the new subtank it seems to be gone).
I have checked absolutely everywhere I can think of, and I'm coming up empty:
-Connections & Leaks: Double-checked everything. No visible leaks anywhere in the lines or junctions.
-Valves: Tested the supply valves at the back. There is zero leakage from them when they aren't activated. Ink flows at a perfectly normal rate and reaches the sub-tank at a good pace. I even replaced the LC supply valve just in case ... no change.
-Sub-tank: Replaced the second sub-tank entirely with a brand-new one. The issue persisted. Subtank sensors are working good.
-Lines & Captop: Flushed the line manually with a syringe to ensure zero blockages and to check for micro-cracks in the lines for air, performed an air purge, and the cap-top is completely brand new.
-Ink Source: Checked the bottle springs and connectors to ensure it's seating and sealing properly and not drawing air from the bulk system.
Despite a brand-new sub-tank, brand-new valve, new cap-top, and clear lines, it still constantly triggers the LC overflow.
Since these machines rely heavily on complex digital pressure sensors and vacuum/pressure pumps to manage the sub-tank levels, I'm starting to wonder if I'm looking at a mechanical ink-delivery issue or if its a electronic/sensor failure.
For those who service these UCJV units regularly, What are the other known failure points or diagnostic steps for troubleshooting chronic single-channel overflow errors when all the physical hardware has already been swapped?
Just to add one crucial detail on the behavior: the machine doesn’t throw the error immediately upon boot-up. It initializes fine, but after doing 2 to 3 test prints or running 2 cleanings, the error triggers. No matter what I do, it always comes back after the head starts moving or drawing ink. Furthermore, when it actually does manage to print before the error hits, the Light Cyan nozzle check is always half missing.
It always starts with Positive Pressure errors, which quickly cascade into or in combination with a persistent Ink Overflow error. On this latest machine (configured as CMYKLmLcWW), it is strictly throwing the Overflow error on Light Cyan now (It also had a Positive P. Notenough but after the new subtank it seems to be gone).
I have checked absolutely everywhere I can think of, and I'm coming up empty:
-Connections & Leaks: Double-checked everything. No visible leaks anywhere in the lines or junctions.
-Valves: Tested the supply valves at the back. There is zero leakage from them when they aren't activated. Ink flows at a perfectly normal rate and reaches the sub-tank at a good pace. I even replaced the LC supply valve just in case ... no change.
-Sub-tank: Replaced the second sub-tank entirely with a brand-new one. The issue persisted. Subtank sensors are working good.
-Lines & Captop: Flushed the line manually with a syringe to ensure zero blockages and to check for micro-cracks in the lines for air, performed an air purge, and the cap-top is completely brand new.
-Ink Source: Checked the bottle springs and connectors to ensure it's seating and sealing properly and not drawing air from the bulk system.
Despite a brand-new sub-tank, brand-new valve, new cap-top, and clear lines, it still constantly triggers the LC overflow.
Since these machines rely heavily on complex digital pressure sensors and vacuum/pressure pumps to manage the sub-tank levels, I'm starting to wonder if I'm looking at a mechanical ink-delivery issue or if its a electronic/sensor failure.
For those who service these UCJV units regularly, What are the other known failure points or diagnostic steps for troubleshooting chronic single-channel overflow errors when all the physical hardware has already been swapped?
Just to add one crucial detail on the behavior: the machine doesn’t throw the error immediately upon boot-up. It initializes fine, but after doing 2 to 3 test prints or running 2 cleanings, the error triggers. No matter what I do, it always comes back after the head starts moving or drawing ink. Furthermore, when it actually does manage to print before the error hits, the Light Cyan nozzle check is always half missing.
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