I have a 2003 Toyota Camry. A year ago, the key fob died; took it into the dealer who juiced it up. A few days later it died again so returned to the dealer who re-programmed both fobs that came with the car. (I am the original owner.) Guess what? Fob died again so I looked in the owner’s manual to discover a fuse was blowing. After much process of elimination, I discovered the fuse that is blowing is the 7.5 amp located inside the car (versus under the hood). I’ve gotten quick at changing the fuse (trying to buy them by the gross but can only find a 5-pack) which needs to be done anywhere from every couple of hours to actually lasting nearly one whole month. (Guess the stars and planets were aligned.) When this fuse blows, it disables the clock - but the not temperature reading - and reverts always to 1:00; the overhead and inside lights; and the key fob. I’ve experimented with not having the radio on, the air or heat, the cd player, the tape player - all the assessories that maybe are causing the fuse to blow. Regardless of what I have on or off, the fuse still blows AND it always blows AFTER I turn off the engine. My routine is to put the car in park, put on the emergency brake (I even experimented with not engaging the emergency brake), then turn off the ignition. I know the fuse has blown because when I open my door to get out, the overhead light is not on and the fob doesn’t work.
My daughter, a Professor, got me hooked on listening to your radio show a couple of years ago. She is brilliant - she suggested I actually write to you to see if you can shed some light on resolving the problem. By the way, the dealer said they would spend how many hours it would take to try to figure it out but my pocketbook is not deep enough to pay the hourly rate without a guarantee they will find anything. Anyway, I am the one who figured it was the fuse that was blowing. I just don’t know why.
The fuse is blowing because there is a short circuit somewhere. That’s the fuse’s purpose. It blows to protect the rest of the circuit from overheating and possibly causing a fire.
The only way to find the short is to test each circuit associated with this particular fuse. Any good independent mechanic should be able to test the circuits and figure out which has a short. You don’t need a Toyota dealer for this.
The key fob itself is not part of the problem, since it is not physically connected to the wiring system.