Symptoms

1. The print failed, with parts of the model missing.
2. When performing the EXPOSURE CLEANING operation, the screen is obviously foggy.
   
   
   

Possible Causes

1. Added non-UNIZ brand coolant to the cooling system.
2. After prolonged use, the white adhesive at the water pump sensor dissolves.
3. After prolonged use,  the white adhesive inside the cooling board dissolves.
   

Diagnostic Steps

1. Added non-UNIZ brand coolant to the cooling system.

1. Typically, there should be no coolant loss during operation. If you find needing to add coolant, it's crucial to first check for any potential leaks in the cooling system. For troubleshooting methods, please refer to the following link: Coolant Leakage.
   
2. After resolving the leakage issue, clean the cooling system with water until it becomes transparent. Then, refill the cooling system with UNIZ brand coolant. Please refer to the video tutorial for specific operations: Cleaning cooling board
   
   

2. Check whether the white adhesive at the water temperature sensor is dissolved.

1. Turn off the power switch and disconnect the power cord;
   
2. Drain all the coolant. Please refer to the link for drainage instructions: How to drain coolant.

1. Disconnect the connector between the hose and the water tank, and turn the black water tank cover counterclockwise to open the water tank;
     
   
   
2. Observe whether there is any dissolution inside and outside the water tank where the water temperature sensor is located as shown in the picture;
   
   
   
   
3. If there is dissolution, please refer to the video tutorial to replace the new version of the water temperature sensor (because some operations have been completed in the early troubleshooting stage, please jump to 1 minute and 30 seconds to start watching): Replace the temperature sensor 3.0,  If there is no dissolution, please skip to step 3.2.

3. Verify whether the cooling board white glue is dissolved

1. Turn off the power switch and unplug the power cord;
   
2. Drain all the coolant. Please refer to the link for drainage instructions: How to drain coolant.

1. Remove the front panel of the printer;
   
   
   
   
2. Unscrew the nuts on both sides of the cooling plate by hand or with the help of a hemostatic forceps, disconnect the hose from the cooling plate, and use a tissue to wipe off the remaining coolant;
   
   
   
   
3. Peel off the shading tape on the screen, unscrew the screws on the cooling board, disconnect the screen wires, and gently push the cooling board up from below with one hand to facilitate its removal.
   
   
   
   
4. Observe the status of the cooling board. If the foggy is severe and the white glue on the side is dissolving as shown in the picture below, please continue to follow the steps to replace the cooling board;
   
Since the LCD screen is fixed to the cooling board through adhesive, generally speaking, the screen needs to be replaced simultaneously when replacing the cooling board.


5. Lay the new cooling board flat and unscrew the nut at the joint;
   
   
   
6. Pour coolant into the joint;
   
   
   
7. Shake it thoroughly to make the cooling board fully immersed in the coolant to avoid air bubbles hanging in it after installation ;
   
   
   
8. Please refer to the video tutorial for the remaining steps (because some operations have been completed in the early troubleshooting stage, please jump to 2 minutes 1 8 seconds to start watching): Replacement of the LCD screen cooling board.

1. Use alcohol to clean the cooling system until the alcohol becomes transparent, then refill it with UNIZ brand coolant. Please refer to the video tutorial for specific operations: https://youtu.be/kNk-VwTvOQ0.
   

Conclusion