Schematic for audio amplifier (Becker?)

Does anyone have or know where to find a schematic (circuit diagram) for the small 2-channel amplifiers used in my 1991 300se? They are the ones behind
the rear seat and could be Becker. Part# is 126 820 18 89.
Are there known common component failures in these amps?
Scott D
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file
Upload is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here. All logos and trade names are the property of their respective owners.