by Chris from Washington » Thu Oct 22, 2026 7:33 am
Howdy welcome to the forum!
For the Kenwood, I don't think I have ever used the pink/black wire.
Are you just trying to turn the amps on/off with the head unit? Does your unit have a blue/white wire? That should be the amp remote wire.
I'm looking at the manual and not quite sure what the pink/black is supposed to do.
For the Sony I've never seen this model before. So I asked AI. Maybe something here will help?
The unit powers on and the disc tries to read, but the buttons stay dead and the panel won’t flip. I suspect the unit is stuck in a startup state because the front panel or its motor mechanism isn’t reporting that it’s in position. That can look like demo mode, since the unit never finishes initializing. A wiring fault is less likely if the unit powers up and reads discs. A bad panel-to-body connection or a jammed or misaligned mechanism seems more likely to me, but I can’t confirm that without seeing the unit.
Things to try
Full reset with the panel handled. Sony’s own guidance for dead faceplate buttons is to turn the ignition off, remove the faceplate, press RESET with a pointed object, and check that none of the buttons are stuck. Then clean the metal contacts on the back of the faceplate and the front of the unit with a cotton swab lightly dampened with rubbing alcohol, reattach the faceplate, and turn the ignition on. A reset erases your settings, which doesn’t matter on a unit that isn’t working anyway. If your panel is motorized and won’t detach, skip the removal and do the reset and contact check only if you can reach the contacts.
sony
Try the remote. If you have the wireless remote, it may work when the front buttons don’t. On other Sony car stereos, demo mode can be switched on or off from the remote, so check whether the remote can open the setup menu and turn demo off.
sony-latin
Re-check the wiring for control and remote leads. On Sony’s Bluetooth models, connecting the microphone to the REMOTE IN jack instead of the MIC jack can leave the unit unresponsive or frozen in demo mode. Your unit may not have a mic, but the same idea applies. Make sure nothing is plugged into a remote, steering-wheel, or control port that shouldn’t be. Also confirm that the constant 12V and accessory leads aren’t swapped and that the ground is solid. Test it on the bench with a known-good 12V supply and ground to rule out the car’s wiring completely.
sony
Check the mechanism. With the unit out of the dash and powered, see whether the panel motor tries to move at all. If it hums but doesn’t move, or if the panel is physically blocked or off its track, that could explain the lockup. Look for a loose flex cable or a ribbon connector between the front panel and the main board, which is a common failure on older units.
If none of that works
An internal fault on the front-panel board or the mechanism would need a repair shop or a replacement part, and on an older unit this often isn’t worth the cost. A second M8810 for parts might be cheaper than repair.
Howdy welcome to the forum!
For the Kenwood, I don't think I have ever used the pink/black wire.
Are you just trying to turn the amps on/off with the head unit? Does your unit have a blue/white wire? That should be the amp remote wire.
I'm looking at the manual and not quite sure what the pink/black is supposed to do.
For the Sony I've never seen this model before. So I asked AI. Maybe something here will help?
The unit powers on and the disc tries to read, but the buttons stay dead and the panel won’t flip. I suspect the unit is stuck in a startup state because the front panel or its motor mechanism isn’t reporting that it’s in position. That can look like demo mode, since the unit never finishes initializing. A wiring fault is less likely if the unit powers up and reads discs. A bad panel-to-body connection or a jammed or misaligned mechanism seems more likely to me, but I can’t confirm that without seeing the unit.
Things to try
Full reset with the panel handled. Sony’s own guidance for dead faceplate buttons is to turn the ignition off, remove the faceplate, press RESET with a pointed object, and check that none of the buttons are stuck. Then clean the metal contacts on the back of the faceplate and the front of the unit with a cotton swab lightly dampened with rubbing alcohol, reattach the faceplate, and turn the ignition on. A reset erases your settings, which doesn’t matter on a unit that isn’t working anyway. If your panel is motorized and won’t detach, skip the removal and do the reset and contact check only if you can reach the contacts.
sony
Try the remote. If you have the wireless remote, it may work when the front buttons don’t. On other Sony car stereos, demo mode can be switched on or off from the remote, so check whether the remote can open the setup menu and turn demo off.
sony-latin
Re-check the wiring for control and remote leads. On Sony’s Bluetooth models, connecting the microphone to the REMOTE IN jack instead of the MIC jack can leave the unit unresponsive or frozen in demo mode. Your unit may not have a mic, but the same idea applies. Make sure nothing is plugged into a remote, steering-wheel, or control port that shouldn’t be. Also confirm that the constant 12V and accessory leads aren’t swapped and that the ground is solid. Test it on the bench with a known-good 12V supply and ground to rule out the car’s wiring completely.
sony
Check the mechanism. With the unit out of the dash and powered, see whether the panel motor tries to move at all. If it hums but doesn’t move, or if the panel is physically blocked or off its track, that could explain the lockup. Look for a loose flex cable or a ribbon connector between the front panel and the main board, which is a common failure on older units.
If none of that works
An internal fault on the front-panel board or the mechanism would need a repair shop or a replacement part, and on an older unit this often isn’t worth the cost. A second M8810 for parts might be cheaper than repair.