Cause: DC output of the power amplifier is abnormal.Supplementary information: The protection function worked due to a DC voltage appearing at the speaker terminal. Acause could be a defect in the amplifier.Turning on the power without correcting the abnormality will cause the protection function to work in 3 seconds and thepower supply will be shut off.2-2. When the protection function worked due to a short between speaker terminals.2-3. When the protection function worked due to abnormal DC output.Cause: The line between speaker terminals is shorted.Supplementary information: As the excess current is detected after operation of the speaker relay, the shorted speakerterminal and the connected speaker can be identified.Turning on the power without correcting the abnormality will cause the protection function to work immediately and thepower supply will instantly be shut off.AD value when the protection function is workingCause: The voltage in the power supply section is abnormal.Supplementary information: The protection function worked due to a defect or overload in the power supply.Turning on the power without correcting the abnormality will cause the protection function to work in 1 seconds and thepower supply will be shut off.AD value when the protection function is working2-4. When the protection function worked due to abnormal voltage in the power supply section.Cause: The temperature of the heatsink is excessive.Supplementary information: The protection function worked due to the temperature limit being exceeded.Causes could be poor ventilation or a defect related to the thermal sensor.Turning on the power without correcting the abnormality will cause the protection function to work in 1 seconds and thepower supply will be shut off.* For detection of each protection function, refer to main menu described later.AD value when the protection function is working2-5. When the protection function worked due to excessive heatsink temperature.● History of protection functionWhen the protection function has worked, its history is stored in memory as backup data.Even if no abnormality is noted while servicing this unit, an abnormality which has occurred previously can be definedas long as the backup data has been stored.The history of the protection function will be initialized when self-diagnostic function is cancelled with “24-2. PRESETRESERVED” (Memory initialized) menu selected.28HTR-2064/NS-B20/NS-C20/NS-SWP20HTR-2064/NS-B20/NS-C20/NS-SWP20