Problem with key fob - Smart Roadster

[Tony2or4]

Hi guys.

Got a strange problem with the key fob for my Smart Roadster Coupé.

Been working perfectly from new (getting on for 10 years old), and I've changed the fob battery a couple of times, each time as a precaution, well before the battery actually went flat.

Then one day, suddenly, the fob refused to either lock or unlock the doors, although pressing the fob button makes the indicators flash as normal.

Checked the fob battery voltage - was fine, but fitted a new battery anyway, but the problem remains.

The spare key works perfectly.

Any ideas, folks?

Thanks in advance for any input.

Tony.

[ch427]

Normally its a case of reprogramming the fob but in your case the lights flash which suggests the system is seeing the signal.
Reprogramming may need diagnostic equipment on this model so its difficult to know what to suggest apart from a diagnostic check from maybe a mobile locksmith?

[Mr2Mike]

Seems to be a very common problem on Smarts, exactly the same thing happened to my bosses For Two. We did some research and read somewhere that the SAM unit (effectively the body control module) has a software bug that causes it to lose sync with a keyfob after a certain (large) number of operations and it requires the MB diagnostic kit to re-sync it. How true this I don't know, but we found large numbers of people posting on Smart forums with the same issue.