TA7317 protect circuit in NAD 319

[ManosR7]

If the amplifier goes into protect mode, there is a fault at the amplifier output stage.
This may be sensed correctly or, more likely, incorrectly by the protection circuit as
discussed in this thread.
Have you read previous posts and particularly #6 and #33?

Yeah i read them... so is those components faulty by the factory or cause of the heat? I already read in other places also they have a flaw (NAD 317/319) in their making. Its quite good that i have a place to focus rather than try all the components with a multimeter to see what is broken! So all the fuzz is on the main board if i understand correct, right? I dont have it open now to write the codes but in the main board left side it haves 6 Large black Capacitors and the only thing i saw that was a little strange was a brownish like glue thing on their bas but they wasn't blown... One thing for sure is when i fix it i will make a cover with 2 12 cm Fans in each side to extract the heat (12v). or i will buy a normal 220v it will help i guess... Can someone send some photos? It will be very-very helpfull

 

[jango2]

I arrived at this post because a Marantz 75SR1020/1A is in protect mode. This I discovered after having to change a faulty driver IC (An7062) which was not driving output transistors with signal. Replacing that solved 1 problem, output transistors were now producing centre rail swing. No errant DC centre rail voltage observed to justify protection mode.
The TA7317P in my amp would only switch the relay on if i shunted it's muting circuit's 150K resistor with a 12K resistor. Voltage at pin 8 (power on delayed mute) was 0.6 instead of 1.3. This is derived from pin 9 (3V supply via a 150K ohm resistor and 47 uF RC combination.
The problem lay with the voltage at substrate pin 5. It was supposed to be -0.8V but was reading 0V. A 10K resistor (designator RN18)supplied -Vcc (-44V) to pin 5. This was open. replaced and all is fine.
Image https://www.facebook.com/photo.php?...003019530.7279.100000728915080&type=3&theater

An externally hosted image should be here but it was not working when we last tested it.

 

[korpberget]

NAD 317 here.
Realays were just clicking fast. Green/yellow flicker. Totally unstable.
Changed just about all the elctrolytics on the power pcb plus 3 of the lifted resistors and speaker relay.
Yes. I messed up the points two times and had to make jumpers p2p. Cap C220 had open +51 V to right amp board. Went into protection.

Gonna replace zeners D658 and D657. Theyre working but are not lifted.
Seems to work fine now