Hello everyone,

my car amplifier was draining too much battery so i decided yesterday to open it up and check whats going on.

I have found a blown component (voltage reference ic i suppose) but i dont know the specifications. On the ic is written: ZDW 39

The system is VW Dynaudio, Lear amplifier. There is no schematic on the web unfortunatelly.

Thanks in advance

 

Any help?
ZDW =
SM5Z12A
SGS-Thomson Microelectronics
SOD-6
Zener diode
12V±2%, Izt=100mA, 5W

 

Might want to zoom out a bit on that second picture so we can see a bit more of the surrounding circuitry.

 

@twohats there are two more components with same mark (ZDW39) on the board. So o took both of them out of the board and tested them in diode mode. There are no readings at all. I got readings only in resistance mode, ande resistance is pretty high in M Ohms. Zener diode should have readings in diode mode? Correct me if i'm wrong.

@Ylli i will take some pictures on the weekend. There are 3 same components on the board, 2 good and one blown just like on the picture. So i decided to change their position and i have noticed that those 3 are for low, mid and high tones.

 

there are two more components with same mark (ZDW39) on the board. So o took both of them out of the board and tested them in diode mode. There are no readings at all. I got readings only in resistance mode, ande resistance is pretty high in M Ohms.

Might be a MOSFET. What you did post of the layout looks like it might be an configured as an amplifier.