Smart Fortwo Key Fob Dead: Central Locking System Down

Had a similar issue with my 2015 Smart ForFour last month. The remote locking system failed completely, showing the same dashboard warning. After diagnostic testing, the problem was traced to corroded wiring connections in the driver side door, where moisture had damaged the central locking control module. The key fob itself was working fine, just the signals werent reaching the security system. While the repair sounds simple, accessing the control module required partial door panel removal and special tools to replace the damaged connectors and wiring harness. This is a known weak point in these models. The issue can escalate if left unattended, potentially affecting other electrical systems connected to the central control unit. Having door locks stuck in one position is also a safety concern. The repair process took about 4 hours at the shop. They needed to: Run full diagnostic scan, Remove door panels, Replace corroded wiring connectors, Test keyless entry system functionality, Recalibrate central locking module Recommend getting it checked soon before moisture causes more extensive damage to the car alarm and locking systems. Make sure the shop has experience with Smart electrical systems, as proper diagnostic equipment is essential for this repair.

Thanks for the detailed explanation. I faced almost the exact issue on my Smart Fortwo last year. The locking mechanism started acting up and the security system went haywire. After checking several repair shops, I also found it was related to moisture damage in the wiring, but in my case it was near the trunk area. The key fob signals were inconsistent at first, then the keyless entry stopped completely. Really curious to know what you ended up paying for the full repair? In my case, they also had to replace additional connectors they found corroded during the inspection. Wondering if youve had any problems since the fix?

Thanks for asking about the repair costs. The central locking issue was successfully fixed last week, and the keyless entry system is working perfectly now. The mechanic found a faulty cable connection near the fuse box that was causing the problem, much simpler than initially feared. The total repair cost came to 95€, which covered the diagnostic testing and fixing the defective component. This was a relief since I was worried about potentially needing a complete replacement of the locking mechanism or more extensive wiring repairs. No issues at all since the fix, the car locks respond immediately to the key fob signals, and the dashboard warning has disappeared. The security system is also functioning as it should. Definitely worth getting it sorted quickly before moisture could cause more extensive damage to the electrical connections.

I took my Smart to the shop yesterday after reading these responses. You were all right, it was indeed a wiring issue, though in my case the problem was isolated to the passenger door locking mechanism. The mechanics found corroded connectors causing the key fob signals to fail. The repair took about 3 hours and cost 180€ total. They had to: Test the car alarm system, Replace damaged wiring, Install new door lock actuators, Reprogram the central locking module More expensive than your repair since they found additional issues during inspection. The remote locking is working perfectly now and the dashboard error is gone. Good thing I got it fixed before the rainy season, the mechanic mentioned the moisture damage would have gotten much worse. No regrets getting it done professionally rather than attempting DIY fixes on the security system. Having working door locks is definitely worth the investment for safety and convenience.