AMT Datasouth Accel-7350, Service Manual

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Troubleshooting Guide
Appearance Checks
Localize defective parts such as broken switches and levers, damaged FFC cable, loose
connections, burned components or blown fuses.
Functional checks
Define the defective functional block without disassembling the printer:
• Power-on initialization check (Checking printer power)
• Display indicator check (lamps operate abnormally)
• Checking on the error messages
• Performing self test check
• Sending printable characters from the host system to check the output (Head
Adjustment Lever)
• Checking function after Program ROM replacement
• Line feed control function check (Reverse line feeding stops after exceeding 22
inches)
Voltage check on the test points specified on Main PCB:
(Remove the top cover and lift the mechanism. Then inspect from the rear side.)
• +5V(Vcc) No.32 pin of U8 (OPTION FONT) of the Main PCB.
• +40V The left side lead wire of the resistor R209 of the Main PCB.
Note:
When the interlock SW is OFF, the output of this point is open.
When the interlock SW is ON, the output of this point is 40V.
Components checks
• You can perform component level repairs using voltage/ampere meters,
Oscilloscope.
• You may be required to understand the electric component characteristics and the
operation principles, before you make any repairs. For the power supply PCB, many
details are provided for your troubleshooting aids.