Altima immobilizer error

I had a similar problem with my Nissan Altima, although it's a slightly older model. The symptoms you describe, especially the engine starting briefly and then cutting out, sound very familiar. Did anything happen before this started? Like, did you recently replace the battery or have any work done on the car's electrical system?

Thanks for the quick reply! No, I haven't done anything recently to the car's electrical system or replaced the battery. It just suddenly started happening one morning. The anti-theft system seems to be doing its job a little too well, haha. Any thoughts on whether it really could be the key programming, or is there something else I should check before I potentially waste money?

Given that it happened suddenly and both keys are affected, it does point towards a potential immobilizer malfunction. While there might be other causes, the error code and symptoms align with incorrect key programming. To be certain, I recommend taking it to a workshop with the appropriate diagnostic tools. They can properly diagnose the immobilizer system and reprogram the keys if necessary.

Okay, thanks a lot for the advice. I took it to a local workshop and, you were right, it was a key programming issue! They reprogrammed the key and charged me 45€, all sorted now. Cheers!