Car Amplifier have power but no sound. Please help me

bro i found something!
when i measure the voltage of diodes so there is 3.30V in D510 and 0.60V in D511.
and i also measure the voltage of those big resistors so there is 15V in left side Resistor and 19V in right side resistor.
And when it short circuited, spark came out from the left side.
 
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No. One produces the +15v for pin 4 of the op-amps and the other produces -15v for pin 11. The attached amp is similar.
 

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Trying to fix this without a schematic and proper test equipment is quite difficult, even for an experienced professional.
And that board looks like it's been under water and is likely to have multiple problems.
At some point you need to draw the line...
 
With 18v of rail voltage and a 150 ohm resistor, there is absolutely no reason for the Zener to fail.

When installed, did the two zeners read their rated voltage when measuring the voltage directly across them?

Does the Zener now read shorted?

What was the part number of the Zener you installed?