Clifford Matrix RSIII Issue

I have an RSIII installed in a 2001 Honda CRV EX. It worked flawless for a couple of years. Then last week while leaving work, i tried unlocking but it will not respond to my transmitter. I even replaced the battery in the transmitter and still will not respond. I had to do an overide so the alarm would stop. Imagine the embaresement(sp) when other employees are glaring at you while the alarm goes off. Did I run into some sort of interference like WI-Fi, radar jammers, other security systems in the area? Is there a component that fails after a couple of years? is there any thing I can check on myself before visiting my DEI Installer? My wifes Accord is also experiencing similar issues. Any suggestions and assistance will be greatly appreciated. thank you.     

The system does not respond to my transmitter in close range, even if i place the transmitter inches from the heterodyne antenna. You mentioned solder points. Is it the solder points on the circuit board? Hope my installer does not laugh when i mention this. Thank you for your reply.

Could be Solder joints like gh057 said.....sometimes installers rush to get the job done and a cold solder happens (solder does not penetrate the wire, only "balls" up on it and causes it to become brittle) which causes the wire to break off with only a small amount of vibration-leaving the alarm with no power or a malfunction......I think every installer has had that happen to him at least once in his lifetime.