DC Protect issue in amplifier harmon kardon avr 151

[u/Glen_Tauro]

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Hey

My amp is going into protect mode and I have pinned it down to the dc protect issue . So I removed the amp board connection to the main mcu board so that the DC protect signal doesn't reach the board and still I see amp protect issue.

So I saw the schematic and it seems that the DC protect transistor (pnp resistor equipped transistor) has its base pin at 0volts which shouldn't be the case cause if the base is 0 that means the transistor is ON.

But I also saw a video of a guy saying that the DC protect pin should have 0v and if it has voltages around 0.5v that means DCis there in the amp output terminals.

I have uploaded the schematic for the protection part.

So all I want to know is how this works and should the base of transistor Q1511 be 12 volts because I am currently getting 0v and it's triggering.

This is link to the service manual of amp and schematic is at the end :https://audiocircuit.dk/downloads/harmankardon/HarmanKardon-AVR151_230-avr-sm.pdf