A UV printer may occasionally fail to complete its carriage reset after startup.
The typical symptom is that you press the reset button, the carriage moves slightly to the right, but it does not return to the normal home position.
At the same time, the printer may also lose its flash-spray function, and other operations cannot continue.
This type of problem is usually related to one of several electrical or control components.
Common Symptoms
You may notice:
- The carriage only moves a short distance after pressing reset
- The carriage does not return to its normal home position
- The printer does not complete initialization
- Flash spraying does not work
- Other machine functions remain unavailable
- The printer appears to stay stuck during startup
When this happens, the issue is more likely related to the control system than to the ink or printing settings.
1. Check the Switch
A faulty switch may prevent the printer from detecting the correct carriage position.
If the machine cannot receive the expected position signal, it may stop the reset process before the carriage returns home.
Check whether the switch:
- Is physically damaged
- Responds normally
- Has a loose connector
- Has a broken cable
If the switch is confirmed to be faulty, replacement may be required.
2. Check the Carriage Board
The carriage board controls signals related to carriage movement and other functions.
If this board develops a fault, the carriage may move slightly but fail to complete the reset sequence.
Possible signs include:
- Abnormal carriage movement
- No flash spraying
- Failure to initialize
- No response after pressing reset
Inspect the carriage board and its connections.
If another known-good board is available, replacing it temporarily can help determine whether the board is the cause.
3. Check the SCSI Cable
A damaged or loose SCSI cable may interrupt communication between the printer’s control components.
Check the cable for:
- Loose connectors
- Bent pins
- Visible damage
- Poor contact
- Broken internal wiring
Reconnect both ends securely and test the printer again.
If the cable looks damaged or communication remains unstable, replace it with a compatible cable.
4. Check the PCI Card
The PCI card may also be involved in sending control signals to the printer.
If the card fails, the machine may not properly complete the reset command.
Check whether:
- The card is installed securely
- The connector is clean
- There is visible damage
- The printer recognizes the card normally
If possible, test with a known-good replacement card.
5. Check the Servo Board
The servo board is another possible cause of abnormal carriage movement.
If it cannot correctly control or drive the carriage motor, the carriage may move only slightly and then stop.
A faulty servo board may cause:
- Incomplete carriage reset
- Abnormal movement
- Failure to return home
- No further machine response
If the switch, carriage board, cable, and PCI card have already been checked, the servo board should be inspected next.
A Simple Troubleshooting Order
For this type of startup problem, you can check the machine in this order:
- Inspect the reset-related switch
- Check all cable connections
- Inspect or replace the SCSI cable
- Check the carriage board
- Check the PCI card
- Check the servo board
Replacing several parts at the same time can make it harder to identify the real fault.
A step-by-step Printer Troubleshooting process is usually more effective.
Final Thoughts
If a UV printer carriage only moves slightly after pressing reset and the machine also loses flash spraying, the problem may be related to the switch, carriage board, SCSI cable, PCI card, or servo board.
Start with the easiest checks first, especially connectors and cables.
If those look normal, test the control boards one at a time until the faulty component is identified.