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SA-8100 protection circuit issue

Right, so where should I be looking to find why the relay is staying open and in protection mode? Is there a list of what the readings should be on each pin of the protection board?
 
Here are the protection board pin voltages:
Pin: voltage
1: 0
2: 0
3: -20mV
4: -20mV
6: -13V
7: 0
9: +3mV
10: -14mV
11: -20mV
12: -5mV
14: +34.3V
15: +34.3V
16: +34.2V
17: +7.36VAC

Everything seems to be as it should be except for pin 14.
 
Here's more info. Looked at the circuit diagram in the service manual and traced the signal back from pin 14. Here's a list of what I measured, expected value from the diagram and what I measured.

Q7 C, +8V, 34.3V
Q7 E, +7.9V, 0V
Q7 B, +8.6V, 0V

Q6 B, -0.7V, +0.65V

Q5 E, +17V, +5.25V
Q5 B, +20.6V, +4.6V

Q1 C, +20.6V, +4.35V
Q1 B, ??, +3mV

Obviously none of these values are correct all the way back to Q1 collector. Is Q1 the culprit? I did replace that with a new KSC1845FTA.
 
R25: 3.87 kohm, spec is 3.9 kohm
R23: 7.83 kohm, spec is 8.2 kohm

turned on and measured voltages at Q6
E: 0
C: +3.7mV
B: +647mV
 
Pulled q1 and q2. Turned the unit on and it did not come out of protection. I kept the original 2SC857K transistors, so I put those back in just to see, and same result. It did not come out of protection. Seems like q1, q2 are not causing the problem.
 
damn ..its a tough one ..
have you checked the diodes ?
what voltages at q3 and q4 ?
something is pulling the voltage down and its hard putting a finger on it
 
Here are q3 and q4 readings:

Q3
E: -600mV
C +5.2V
B: -3mV (varies a lot from -7 to +5 mV)

Q4
E: -500mV
C: +8V
B: +0.12V

I have not checked the diodes, I've forgotten how you check those?
 
start with q8 .
no power .
dmm on diode test . should show about 600mv black on banded end red on other . swap leads and should be OL or whatever your meter says for open circuit .
 
Diode readings:

D8: 701, D7: 712, D6: 711, D5: 700, D4: 696, D3: 750, D2: 697, D1: 702. All showed open in the opposite direction.
 
Yes, I changed all 6 capacitors on the board. I'm pretty sure I put them in correct as I followed what was printed on the board itself for + orientation. How do I check if they are in right? Put red lead on + and black on - and check capacitance?
 
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