So my subwoofer has been working fine for the past 1 year but recently it started breaking up. I start the car and the subwoofer is not working. The only way to make it start working is if i go in the trunk and press lightly with my fingers on the diaphragm. Afterwards , it shuts off. But it only shuts off when there is no music playing , for example the few seconds of silence when song ends and another song starts. At that point i have to go back in the trunk and press on the diaphragm again for the subwoofer to start again. Any idea what might be the cause? I messaged a guy that knows something about subwoofer and he said i need another subwoofer , but didn't give me any details...
It seems as if the EMF generated by the woofer's motor assembly when you touch the cone is triggering the amp for some reason. I haven't seen this, but I have seen issues with the 12V 'trigger' connection on some amps. You didn't mention your amp's make and model#, so I'm speculating. If you do have a 12V amp trigger from the head unit (I have mine connected to a relay to switch on multiple amps), check the voltage and be sure the connection has good integrity.
If your subwoofer has it's own amp built in to the cabinet that amp isn't turning on as it should. As mentioned above when you move the cone you are generating a voltage that the amp detects and turns itself on.
Even if the amp isn't part of the sub cabinet it may not be turning on. There may be an indicator on the amp. Connect another woofer to the amp. If the amp is bad you will have the same problem.