I have a 2005 Mazda 6 with a remote starter installed at the mazda dealership back when I bought it. Never had an issue until back in January when it wouldn't start the car once in a while. The weather got warm and I forgot about the issue until the unlock/lock started failing intermittently too. I replaced the batteries, still had the issue. Tried the backup key fob, same issues. I reprogrammed the key fob successfully... Remote starter and unlock/lock worked fine when I was at home. Next day at work, fails again. Is this a signal issue or the key fobs are just getting old? I don't want to invest money in new key fobs only to find out there's something wrong in the car itself. Is there a way to test it without shelling out money to the dealer? The only possible electrical-related thing I can even think about was the car battery was disconnected for a while when I changed the spark plugs last November.

 

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