850.4 kicker

Pin 8 and 11 are tied to the soft start circuit. The voltage on Pin 3 is high.

Measure DC voltages around U2,Q1,Q7,Q8 from power GND and post.

A good close up pic of the U2 and the soft start circuit which includes Q3,4,5,6 would be helpful and an overall pic of amp and amp cover would be helpful to determine model version. This amp spanned the years from 2004 to 2011 and have some changes to the circuitry year over year.
 
This is a zero ohm resistor which I believe is to connect spkr and pwr GND's. To confirm measure with an ohmmeter from spkr to pwr GND and if you read 10 ohms my assumption is correct.You will want to replace 10 ohm with 0 ohm resistor, but for testing purposes leave it in.

Q32/33 may be the +/- 15 volt regulated supply, which tend to run hot. Once they are mounted to chassis with a pressure bar they will be fine.

I will check schematics tomorrow and get back to you.
 
Silkscreen is gone in that area due to corrosion .I can see a black band in the center of the resistor.I install a 10ohm in there for test and amp powers up ok.I get good audio on all channel but Q32/33 heats up fast.Is that normal for this amp?

R36 is an 11K ohm 1/8 watt 1% resistor, which if out of value would shut down the U2-TL494.If the resistor in question is R36 than it should have 2 brown bands a black band(in the center), a red band and a brown band.

I'm not sure how replacing it with a ten ohm resistor would work, is it possible you replaced R36 with a 10k ohm resistor?
 
This is a zero ohm resistor which I believe is to connect spkr and pwr GND's. To confirm measure with an ohmmeter from spkr to pwr GND and if you read 10 ohms my assumption is correct.You will want to replace 10 ohm with 0 ohm resistor, but for testing purposes leave it in.

This is incorrect. the 0 ohm resistor I'm thinking of is R73. R36 should be an 11kohm 1/8w 1% resistor.

Q32/33 may be the +/- 15 volt regulated supply, which tend to run hot. Once they are mounted to chassis with a pressure bar they will be fine.

Q32/33 are in fact the regulators and as I said they do get hot but once the are clamped done in chassis they will be fine.


I will check schematics tomorrow and get back to you.
 
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There are two 1N4148's attached to Pin 3,to be sure I would need the locator number for diodes.

The diodes are most likely D6 and D9-1N4148's connected to Pin 3 of U2-TL494. To determine check with ohmmeter from anodes to Pin 3.These typically don't fail.

I don't have a schematic handy. Are the color bands on R36 unreadable? Is this resistor connected to Pin 1 by any chance?
 
I will check tomorrow what it is connected to.Resistor i used is 10 ohms.The black band in the center made me think brown black black.I think you right on the value.The body color of the resistor is light green which i usually see five bands on.It is the only one in that color .I will put in a 11k to see what happen.
 
Perry is correct and applying signal to the front channel RCA'S will feed signal to Rear channels, and allow for seperate pair of inputs.

Using a 10kohm resistor will shift the threshold point and will lower the thermal shutoff temperature slightly. I don't think it will be significant. Testing into thermal protection (clamped in chassis) for a couple of cycles will prove if resistor needs to be replaced with original value.