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fob stopped working after battery replacement

319 Views 3 Replies 2 Participants Last post by  VStar650CL
Hi

I replaced batteries on both intelligence key fobs. due to both reported low battery.
one of the fobs doesnt lock or unlock the car anymore however if i put the fob close to the start button the engine will turn on
I tried replacing the battery again with a second new one still same issue.

I took the car and keys to the dealership they said they tried reprogramming it but they noticed the antenna on the key is faulty.
I took both keys apart and i dont see any missing or any physical damage to any components. i did a simple continuity&resistance on the bigger components and compared working and nonworking fobs and they are identical. no components are loose either when i push on them.

any ideas which area to look at if the dealership are telling the truth that the "antenna" is faulty.
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It's probably the antenna driver circuitry that's bad and not the antenna itself. All Nissan dealers have at least one "required" special tool for checking whether a fob transmits or not, so I'm sure they simply put yours on the Tech-II or the fob checker and found it wasn't transmitting. The "emergency start" circuit using the button is a completely different function that uses RFID and will work even with the fob battery removed, so a blown transmitter won't prevent that from working.
i assume the antenna driver circuitry is controlled by the black square chip ?
Yep, the micro controls pretty much everything in there except the emergency start RFID.
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