This kind of problem happened to me last 3 days. The problem solved after reading comments from here. My Vios 04 is using COBRA alarm with immobilizer (black color), both of my remote was not functioning. What did I do to disarm my cobra alarm, I just unlocked the door using key manually. Once I opened the door, the alarm is automatically triggered. Then I turn on the ignition key and let all the lights on my dashboard are off after few seconds, then I touched the immobilizer on its pad. It worked to disable the alarm. I called Cobra TTDI, they said no need to duplicate the remote. Just bring it to their centre then they will repair. It will be cheaper than duplication. I will bring it to them soon..