I couldnt find any info on the forum, so for you guys and gals out there trying to replace the AMSS buttons (who tend to die), and stumbled upon amongst others a russian guy replacing them ....here s the procedure to acutally get them working : They need to be resistant (ohmy), so just a contact button will not work properly, you need to add a resistor. Apparently the AMSS pcb / IC does not expect to just get a closed contact, it expects a current or current peak and not just a "shortcircuited connection".
1. the original buttons are NOT contact buttons, meaning : they make contact but contain a resistance through which they make the contact (I dissected one)
2. to replace them : basic 2 pin (or 4pins if you place them diagonaly) contacts, 7mm height is perfect (to fit the "chrome" buttons on top)
3. remove the old buttons, and chrome caps
4. follow the circuit on the mini pcb and CUT the three paths that go from the upper pin (close to the leds) to one of the wires
4 bis : the middle is a very short one : only 2 solder dots and 2mm between them, you cal also just cut the bridge on the other side - the 3rd one also has a bridge (those are the two metal things going up)
once you ve done that you will need : 3 x 15 to 20ohms resistor (by trial and error i found this margin works all the times, lower and you get weird results (like when you only put new buttons in) : leds running from 1 to3 nd vice versa without making any sense. And basic momentaniouc 4 or 2 pin (2 pin is easier) contact buttons. 7mm works best because when the chromed buttons are fitted on them they stick out like they should), longer than 7mm and they will stick out too much, shorter and they ll go in too deep.
5. now solder 1 pin of the new buttons (on the bottom, ground, not the side where the leds are) "normally" meaning pin sticking out and soldering it to the circuit, this will keep the button in place.
6 get one end of each resistor in the 2nd pinhole to solder it to the 2nd pin of the new button. remember you cut the rest of the circuitry so it makes no contact anymore to anything.
7. now you will need something to isolate the resitors and resistor wires, since you cant solder them on the button side of the pcb, only on the backside (where all the soldering is going on and where they could short circuit things) - a heatshrinking tubes work fine, but electricians tape over the circuitry with the resistor on top of it works too.
8. solder the other end of the resistor to the appropriate wire (the LBGT colored ones) - you can see where each one goes by following the circuit path of each one (circuit paths you already cut). DO NOT put the resistor on the led and button side of the small pcb, or it wont fit anymore.
This way when pushing the button, in series with the resistor, the IC gets the current peak it expects and reacts to it by activiting AMSS for 1 2 or 3 songs, instead of just behaving irratically,
Before putting everything back : plug the LGBT plug back into the amss pcb itsself, plug in or power up your box and hit play and test the buttons, They should now function as intended : 1 lighting up if 1 is pushed, 2 if 2 is pushed,... and no more odd behaviour. AMSS will now work fine and as intended. ALways good to check it works before putting it in place below the entire chassis. Be careful to put the wires back where they were and in their retainers, together with the STEREO led wires.
Hope this helps those who spend time effort and scratched hands and fingers desoldering, rebelting,.... but cant get AMSS to work despite replacing the buttons.
(if this were to be a double, any moderator reading this please delete
)
1. the original buttons are NOT contact buttons, meaning : they make contact but contain a resistance through which they make the contact (I dissected one)
2. to replace them : basic 2 pin (or 4pins if you place them diagonaly) contacts, 7mm height is perfect (to fit the "chrome" buttons on top)
3. remove the old buttons, and chrome caps
4. follow the circuit on the mini pcb and CUT the three paths that go from the upper pin (close to the leds) to one of the wires
4 bis : the middle is a very short one : only 2 solder dots and 2mm between them, you cal also just cut the bridge on the other side - the 3rd one also has a bridge (those are the two metal things going up)
once you ve done that you will need : 3 x 15 to 20ohms resistor (by trial and error i found this margin works all the times, lower and you get weird results (like when you only put new buttons in) : leds running from 1 to3 nd vice versa without making any sense. And basic momentaniouc 4 or 2 pin (2 pin is easier) contact buttons. 7mm works best because when the chromed buttons are fitted on them they stick out like they should), longer than 7mm and they will stick out too much, shorter and they ll go in too deep.
5. now solder 1 pin of the new buttons (on the bottom, ground, not the side where the leds are) "normally" meaning pin sticking out and soldering it to the circuit, this will keep the button in place.
6 get one end of each resistor in the 2nd pinhole to solder it to the 2nd pin of the new button. remember you cut the rest of the circuitry so it makes no contact anymore to anything.
7. now you will need something to isolate the resitors and resistor wires, since you cant solder them on the button side of the pcb, only on the backside (where all the soldering is going on and where they could short circuit things) - a heatshrinking tubes work fine, but electricians tape over the circuitry with the resistor on top of it works too.
8. solder the other end of the resistor to the appropriate wire (the LBGT colored ones) - you can see where each one goes by following the circuit path of each one (circuit paths you already cut). DO NOT put the resistor on the led and button side of the small pcb, or it wont fit anymore.
This way when pushing the button, in series with the resistor, the IC gets the current peak it expects and reacts to it by activiting AMSS for 1 2 or 3 songs, instead of just behaving irratically,
Before putting everything back : plug the LGBT plug back into the amss pcb itsself, plug in or power up your box and hit play and test the buttons, They should now function as intended : 1 lighting up if 1 is pushed, 2 if 2 is pushed,... and no more odd behaviour. AMSS will now work fine and as intended. ALways good to check it works before putting it in place below the entire chassis. Be careful to put the wires back where they were and in their retainers, together with the STEREO led wires.
Hope this helps those who spend time effort and scratched hands and fingers desoldering, rebelting,.... but cant get AMSS to work despite replacing the buttons.
(if this were to be a double, any moderator reading this please delete
)Attachments
Last edited: