Brother DP-550CJ, Service Manual

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REPAIR
SERVICE MANUAL
Troubleshooting
3-3
•
Run the appropriate Self Test operation (from the software) for the suspected problem
before attempting any mechanical or electrical troubleshooting.
•
Supply voltage: Check the AC input voltage and DC supply voltage for all sections.
Make sure they meet specified voltage values.
•
Connectors: Check all connectors and make sure they are tight.
•
Fuses: Check for blown fuses (F1 and the thermo-fuse inside the AC adapter).
NOTE:
•
In the logic control circuit, it is difficult to isolate faulty points in areas connected tot he
CPU by the address bus or the data bus. If a suspected problem involves the address
bus or data bus, first check the solder bridge and the cut circuit pattern. If a faulty point
cannot be isolated, replace the peripheral devices or the PCB.
4. Checks After Repair
After completing a repair, check to confirm that the trouble has been eliminated. Also,
record the troubleshooting procedures used for reference.