Faulty Lcd Display; Faulty Led Display - Star Micronics LS-5 SERIES Technical Manual

TROUBLESHOOTING

2-12-2. Faulty LCD Display

Step
1 Check parts with different specifications for problems with
usage, defective installation, breakage, and deformation.
• Main parts to be checked:
(1) MCU PCB, (2) Console assy, (3) LVPS assy
2 (Check main logic board)
Does a normal display appear when the main logic board is
removed?
3 (Check power supply of console assy LCD)
Is the voltage 5VDC between P/J200-A1PIN
4 (Check replacement of MCU PCB)
Does the problem occur after the MCU PCB has been replaced
with a normal one?

2-12-3. Faulty LED Display

Step
1 Check parts with different specifications for problems with
usage, defective installation, breakage, and deformation.
• Main parts to be checked:
(1) MCU PCB, (2) Console assy, (3) LVPS assy
2 (Check power supply of console assy LED) *1
Is the voltage 5 VDC between P/J200-A1PIN
3 (Check LED on console assy)
When the power supply is turned on, does the LED light up?
4 (Check LED ON signal) *1 *2
When the power supply is turned on, is 0 VDC supplied
between the following?
P/J200-A8PIN
P/J200-A9PIN
P/J200-A10PIN
P/J200-B9PIN
P/J200-B10PIN
*1: Check with the connector (P/J111) disconnected from the HVPS.
*2: The LEDs corresponding to the various pins of P/J200 are as follows:
P/J200-A8PIN → LED (1)
P/J200-A9PIN → LED (2)
P/J200-A10PIN → LED (3)
P/J200-B9PIN → LED (4)
P/J200-B10PIN → LED (5)
Check
↔
Check
↔
↔
P/J200-B1PIN
↔
P/J200-B1PIN
↔
P/J200-B1PIN
↔
P/J200-B1PIN
↔
P/J200-B1PIN
– 96 –
YES
To step 2
Check main logic
board.
To step 4
P/J200-B1PIN?
Replace console
assy.
YES
To step 2
To step 3
P/J200-B1PIN?
Replace MCU
PCB.
Replace console
assy.
Measure
NO
Replace or
reinstall.
To step 3
To section 3-1
Processing
completed.
Measure
NO
Replace or
reinstall.
To section 3-1
To step 4
Replace MCU
PCB.