
B–63175EN/03
7. TROUBLESHOOTING
427
Check whether it is a trouble of display or a trouble of the system.
Check what is displayed with the 7–segment LED (LEDM1) on the
controller.
1) If nothing appears
→ See Section 7.2.
2) If a pattern other than “8.” appears
If the status shows the above state, the system is normal.
Therefore, display system may be faulty.
3) If the pattern “8.” appears
It is likely that hardware other than the display circuit malfunctions.
If the message “WAITING FOR CRT DATA” appears on the CRT/MDI,
it indicates that the CRT/MDI has started normally.
If the 7–segment LED (LEDM1) displays a pattern other than “8.”, check
the following:
(1)Confirmation item
Determine which of the following problems are evident.
1. Nothing is displayed on the CRT/MDI.
2. Only the message “WAITING FOR CRT DATA” appears on the
CRT/MDI.
3. A position display appears on the CRT/MDI, and the keys are
ineffective.
(2)Causes and remedies
1. If nothing is displayed on the CRT/MDI.
D The power being supplied to the CRT/MDI is abnormal (check
the power supply).
D The CRT/MDI is defective (replace the CRT/MDI).
2. If only the message “WAITING FOR CRT DATA” appears on the
CRT/MDI.
D Incorrect cable connection (correct)
D Defective cable (repair or replace)
D Defective CRT control unit (replace the base PC board)
D Incorrect setting of CRT link (correct the setting)
3. A position display appears on the CRT/MDI, and the keys are
ineffective.
D Defective cable (repair or replace)
If the 7–segment LED (LEDM1) still displays the pattern “8.”, the system
is operating normally.
It is likely that the CPU card, base printed–circuit board, or DRAM
module is defective.
7.8
WHEN MANIPULATION
IS NOT POSSIBLE
WITH THE CRT/MDI
AND SO ON
Points
Judgement of the point
Causes and remedies
1. When the display system
is in toruble
2. When system is in
trouble