Trafic Key Fob Battery

I know this all too well! Had the same thing with my old Laguna. Sounds like a dead fob battery. Have you tried your spare key? If it works, it's almost definitely the battery in your main key. Also, how many kilometers?

Sorry, the Trafic has about 234544 kilometers. I haven't tried the spare key yet, but I will. If the spare works, should I replace the battery myself, or go to a technician to avoid issues with the electronic systems?

Right, 234k clicks... Yeah, definitely the battery. If the spare works, save yourself the headache and just get the battery replaced. Unless you're confident fiddling with electronics, I'd say pop down to a local garage. It's a ten minute job for them, and they'll make sure it's all synced up properly. Plus, they usually have the right batteries. I tried doing it myself once and ended up with the doors not unlocking! Lesson learned. For peace of mind, get it done professionally. Cost me about 40€ last time. Well worth it!

Following your recommendation, I visited a local workshop. The technician confirmed the key fob battery was depleted. They replaced it, and the keyless entry was restored. The total cost was about 37€, much cheaper than a new key!