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fob stopped working after battery replacement

321 Views 3 Replies 2 Participants Last post by  VStar650CL

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.
Circuit component Guitar accessory Passive circuit component Microcontroller Hardware programmer
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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.
Yep, the micro controls pretty much everything in there except the emergency start RFID.
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