Symptom: The coolant level sensor displays an incorrect coolant level.
Possible Cause: The sensor is damaged, or the float cannot move.
If your coolant level sensor does not display the correct level on the screen, look in the coolant tank to make sure a chip build-up does not block the float from moving freely.
Make sure the coolant level sensor operates correctly:
- Press MEMORY. The upper-right corner of the screen will show the coolant level.
- Remove the level sensor from the tank and move the float to the maximum travel at both ends. The coolant level indicator on the screen should move at a slow pace. It takes approximately (1) minute to move from empty  to full  on the screen, but it starts to move immediately.
- If the coolant level sensor does not operate correctly, unplug the coolant level sensor from the machine. Remove the cover to access the wires of the variable resistor.
- Measure the resistance across the white and black wires [3/4] when the float is up  and when it is down . The resistance should be approximately 371 Ohms when the float is up and 286 Ohms when it is down.
- Make sure that the coolant level sensor RJ12 cable  or M12 cable  is securely connected, and is not damaged.
- If the coolant level sensor continues to read incorrectly, and you have completed the troubleshooting instructions, replace the sensor.