Mindray DC-68, Service Manual

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Troubleshooting of Regular Malfunctions 13-9
13.6 Control Panel Failure
13.6.1 Related Modules or Boards
No. Description Remarks
1 Control panel assembly /
13.6.2 Key Points Supporting Troubleshooting
No. Key Points Supporting Troubleshooting Remarks
1 Backlight of the control panel Confirm whether the control panel is powered on
normally;
2 Key sound of the control panel. Confirm whether the buzzer works normally
3 Response to general function keys on
control panel.
/
4 Response to general key on numeric
key board.
Confirm whether it is numeric keyboard error or
PCBA error.
5 Response to trackball operation /
6 Response to the sliding potentiometer Confirm whether the error of a single sliding
potentiometer or the control panel PCBA is
corrupted.
7 Response to each encoder Confirm whether the error of a single encoder or
the control panel PCBA is corrupted.
8 Self test for control panel test Available to error diagnosis.
13.6.3 Troubleshooting of Control Panel
No. Fault Description Cause Analysis Solution
1 Buzzer alarming Key blocked; Check the control panel for
key block.
2 Some or a certain key fails Errors on key board PCBA or
silicon keys.
Replace key board PCBA or
silicon keys.
3 Some or a certain key on
the small keyboard fails.
Small keyboard assembly Small keyboard assembly
4 Trackball failed or
abnormal
Dirt or obstacles jam in the
trackball groove.
Open and clean the groove
Improper settings of trackball
speed in system preset;
Preset the system
Degenerated trackball
performance
Replace the trackball