I am having a problem with the stereo light not coming on with the reception of a strong FM stereo signal. The stereo light is on the right side of the faceplate. I cannot seem to locate the correct multiplexer circuit schematic of the multiplexer in this radio. While researching I have discovered a number of different multiplexers were used. The one I have my receiver has a number imprinted on the chassis #5791183. I will try to attach a photo of it. It is not an MX600 and the SAMS photofax Set 613-11 is not correct either. Any ideas on getting the correct info on this unit is appreciated.
Not sure how into youtube you are but there is a young man who does a lot of repairs and might have the info you are looking for.
https://www.youtube.com/@AHFixIt