hello everybody, I'm new here, first of all thank to all for the help i found in this forum during the repair of. all my Sony WM.. Today i just changed the belt, cleaned and adjust speed of my WM-EX70. (nice minimal shape and design) (i didn't find azimuth screw on this kind of head) ... everything's fine, good sound quality. except that sometime all the buttons didn't react as expected : Stop button react like Play button... Play react like FF etc...and sometime everything's works well... weird! i have really no idea what can be the cause ! so i would be very grateful if some of you can share their eperience, or tell me what to do merci / thank you. by advance. b
Probably oxidation of the button or switch board. These are all connected together into an array of resistors, which are later measured by the main board. Open it up, remove the flexible switch sub-board, give it a good cleaning with isopropyl and then treat it with DeoxIT Spray Contact Cleaner.
Johny_2000, thank you very much for your advice, I'll check, and clean and come back for the result! because of your picture, i ll also gonna check if the buttons, when they are working wrong are "shifted". Something like : stop=play, play=rew, rew=ff.. I remember that i noticed something like that but i didnt investigate more into this direction. what do you think? btw, thank you, I'll be back
All these malfunctions are caused by increased or decreased resistance between the buttons, which are then incorrectly interpreted by the microcontroller on the board. S902 is the flexible switch sub-board.
wonderful! @johny_2000, merci for this detailed picture of. s902 part i ll clean it as adviced and test if everything come back to normal. by my side i come back soon with good news, hope so ... cheers .
hello @johnny_2000 i finally cleaned the switches as recommended with alcohol and then contact cleaner, and also all the board around the concerned resistors. i didn't take the risk to unstick the soft panel on witch the swithes are located . So I didn't clean them on their back... i didn't notice oxidation or other short circuit cause, they were clean and. looked new ... after the process the wm seems to work much more better (even if once yesterday i experienced again the same bug as before..no. other bug today... ) we'll see, thank you for your help! merci beaucoup. b
little update : after hours of use, it seems everything (buttons especially) is working well. so great! thanks you
