Infiniti FX35 Key Replacement in San Diego County (2003-2012)

Partly. On a 2003-2008 FX35 you can sync the remote buttons yourself by doing an ignition cycle procedure until the hazards flash, then pressing the lock button within a few seconds. That handles lock, unlock, and panic. But the transponder chip inside the key head, the part that actually allows the engine to start, requires professional equipment to program. So you can handle the remote portion at home, but you still need a locksmith for the piece that matters most. We can do both in one visit anywhere in San Diego County.

That fob takes a CR2025. When the battery starts to go, you'll notice the remote range shrinking before it stops working entirely. Use a small flathead to open the fob, swap in a fresh CR2025 positive-side up, and press both halves firmly together until they click. A loose case causes intermittent signal issues that can look like a bigger problem. If a new battery doesn't fix things, the transponder or the factory immobilizer is likely the culprit and a visit from us will sort it out.

Try the backup method first: look for a slot near the steering column and slide the fob into it. If the car starts, the fob battery is too weak for the proximity system to detect it from your pocket. If it still won't start with the fob in the slot, the factory immobilizer isn't recognizing the key. The 2009 smart key requires OBD-II programming, so there's no owner-reset sequence for this one. We see this regularly on calls around San Diego along the I-5 and 805 corridors, and we can diagnose it on-site.

Only the 2009-2012 models have push-button start. The 2003-2008 FX35 uses a traditional transponder key that goes into the ignition, no proximity system. If your smart key battery dies on a 2009-2012, use the hidden emergency blade to open the door, then hold the fob against the start button while pressing the brake to start the vehicle. That backup works even when the battery is fully dead.