Kenwood KAC-PS401m stuck in protection

[Perry Babin]

Output leg of the rectifiers.

DCV on pin 37 of the MCU?

 

[vincegironda]

Which pin is 37?

 

[Perry Babin]

Pin 1 is marked. Count counter-clockwise.

 

[vincegironda]

4.92v dc pin 37

 

[Perry Babin]

Were there any shorted/defective components that were clamped to the heatsink (FETs, output transistors, rectifiers)?

DCV on pin 30 of the MCU?

 

[vincegironda]

Pin 30. 4.9v

 

[Perry Babin]

DCV base of Q34?

DCV on pin 11 of the TL494?

 

[vincegironda]

Pin 11 TL494. 0.432v

 

[Perry Babin]

DCV base of Q34?

 

[vincegironda]

I can't find Q34

 

[Perry Babin]

Can you find Q9?

 

[vincegironda]

Found Q9

 

[Perry Babin]

It should be near Q9. They are connected by R2.

 

[vincegironda]

13.3v at base of Q9

 

[vincegironda]

It should be near Q9. They are connected by R2.

Which leg is connected to R2

 

[Perry Babin]

R2 as simply to give you something to follow.

I need the DCV on the base of Q34.

 

[vincegironda]

Could it be an smd transistor? There are many unmarked

 

[Perry Babin]

It could be. There are only three components connected to R2, R1, Q34 and Q9.

 

[vincegironda]

Here's Q9

 

[Perry Babin]

The resistor marked 472 is R2.