Smart fortwo ~ doors won't lock!!!

[Clarabell]

I have a 53 smart fortwo. After parking it at work this week I tried to lock the doors and they wouldn't lock. I checked them all to make sure they were properly shut, checked the boot and tailgate; all ok. When I press the key fob to lock the door the lights flash 9 times - My husband has checked the manual and the only suggestion was to change the battery in the key fob which I've done and it's still not locking. The mechanism must be working because I can press the button on the dash whilst I'm sat in the car and it locks all the doors, but I then have to use the drivers door to get out which obviously then unlocks that door. At the moment I'm using this method to just lock the boot and passenger door. Any suggestions gratefully received!!

[J500ANT]

Re: Smart fortwo ~ doors won't lock!!!

The key has gone out of sync with the car. You'll need to use the spare, and get the other recoded (by a dealer or someone with the correct kit)

[Jimmyrinse]

Re: Smart fortwo ~ doors won't lock!!!

The key operates by sending a code to the car, the car expects the correct one. If you press the unlock button too many tines out of range of the car the codes wont match and it wont unlock. As suggested try your spare if you have one and sounds like the key needs recoding

[137699]

Re: Smart fortwo ~ doors won't lock!!!

The key operates by sending a code to the car, the car expects the correct one. If you press the unlock button too many tines out of range of the car the codes wont match and it wont unlock. As suggested try your spare if you have one and sounds like the key needs recoding

It's nothing whatsoever to do with how many times you press the buttons whilst out of telhe range of the car.

It is quite simply a bug in the locking code sequence generator algorithm. You have approximately a 1 in 14,000 chance of it happening every time you press the lock or unlock button. Hence the importance of a working spare key.

[tolsen]

Re: Smart fortwo ~ doors won't lock!!!

I am not convinced about the bug theory but more inclined to conclude the out of sync problem is caused by some owners or their children playing with the fobs while out of range with the car. Allegedly, 257 pushes are sufficient to bring a fob out of sync with the receiver.

[BBE]

Re: Smart fortwo ~ doors won't lock!!!

To my knowledge, the bug theory holds true for early versions of the roadster,
but I never heard it as related to the fortwo.
Bjorn

[Clarabell]

Re: Smart fortwo ~ doors won't lock!!!

I need your help again. So, my husband spoke with a mechanic who said to try 2 things before recoding the key. Firstly, put the key in the ignition and turn it to the first position and back again 8 times. This hasn't worked. He also then suggested we disconnect the battery, touch the terminals together and then reconnect the battery, lock and unlock the car and this should fix it but again this isn't working. Instead the car now won't start. There's a few beeps and a key sign on the screen on the dash. Before I phone Green Flag, does anyone have a clue on whats happened and how I can fix it?

[heinkeljb]

Re: Smart fortwo ~ doors won't lock!!!

If you can't unlock the car and even if you get into the car via the boot hatch you still can't dismiss the key symbol from the speedometer dial, then at the very least the key has gone out of sync with the car.

Do you have a spare key you can try? (If not why not? Now you know why you need a spare key!!)

At this point you are not going to be able to do anything unless the keys and the car are brought together with either an MB Star or a WIN Star diagnostic system. These are the two systems which can recode your key and car to work together. There are independant and Main dealers who have this kit - obviously the Independant garages will be cheaper.

John

[Clarabell]

Re: Smart fortwo ~ doors won't lock!!!

Thank you,

The owner I bought it from had lost the spare so I didn't get one. I'll try a main dealer tomorrow.

Claire

If you can't unlock the car and even if you get into the car via the boot hatch you still can't dismiss the key symbol from the speedometer dial, then at the very least the key has gone out of sync with the car.

Do you have a spare key you can try? (If not why not? Now you know why you need a spare key!!)

At this point you are not going to be able to do anything unless the keys and the car are brought together with either an MB Star or a WIN Star diagnostic system. These are the two systems which can recode your key and car to work together. There are independant and Main dealers who have this kit - obviously the Independant garages will be cheaper.

John

[Jimmyrinse]

Re: Smart fortwo ~ doors won't lock!!!

There are 2 codings for the key, theres the unlocking part and the immobiliser part. The steps you tried to remedy the original problem sounds like it has now knocked the immobiliser part out as well which is why the car wont start.

You can get the key recoded without an MBSTAR or WINSTAR but only the unlock part, unfortunately now you will need either of these tools as they are the only ones that can recode the immobiliser.

[137699]

Re: Smart fortwo ~ doors won't lock!!!

The algorithm bug was disclosed by Mercedes to dealers during training sessions for the 450 & 452. The algorithm randomly generates a code which cannot be accepted by the central locking system and it generates a fault which STAR reports as "code is outside of expected range" (or something similar).

I believe it is fixed on the 451 and have not heard of it affecting the 454.

[Red in Missouri]

I found out that this smart car wants to know you have keys in hand before you lock it! so standing outside "unlock" with the remote and they know this. Then "lock" with the remote and it will lock this time.