Muratec F-525, Field Engineering Manual

Page: 290 / 383

4-24
4.13 LCD Failure
Symptom: No display in the LCD.
Suggested corrective action:
1. Verify that the power cord is correctly connected and the power switch is ON.
2. Check for a blown fuse or open circuit on the unit’s internal power supply.
3. Check the DC output voltages from the power supply unit to connector P3 on the main control PCB.
If any of the following voltages are incorrect, replace the power supply.
•
Pin 4, 5 : +5 V
•
Pin 8, 9 : +3.3 V
•
Pin 6, 7, 10, 11, 14, 15 : GND
4. Check the following connectors:
• LCD assembly to the Panel PCB (P52)
• Panel PCB (P50) to the Harness to the main control PCB (P5)
5. Replace the associated PCBs and connector harness.
4.14 General Power Failure
Symptom: Unit will not power up.
Suggested corrective action:
1. Verify that the power cord is correctly connected and the power switch is ON.
2. Verify that the electrical outlet is on.
3. Check for a blown fuse or open circuit on the unit’s internal power supply.
4. Check the DC output voltages from the power supply unit to connector P3 on the main control PCB.
If any of the following voltages are incorrect, replace the power supply.
• Pin 4, 5 : +5 V
• Pin 8, 9 : +3.3 V
• Pin 6, 7, 10, 11, 14, 15 : GND
• Pin 12, 13
: +24 V@Pin 1:5 V
• Pin 12, 13 : +17 V@Pin 1:0 V