Hi I have a 59 plate c220 and noticed yesterday that the unlock button on the key fob no longer unlocks the car and I had to use the key to gain access every time,the lock and trunk buttons do still work ok as do all the buttons on my spare key.

it was working perfectly fine on Saturday with no problems 

ive changed the battery but it still doesn’t work has any body came across this and what may be the problem 

thanks in advance 


The problem is that the small button for the unlock button on the keyfob has been disconnected. If you have a soldering iron, open up the key. Pull out the circuit board. You will see the unlock button. 

It needs to be soldered into the board. 

Have had this happened to me in the past. No need to buy a new key. 

It depends which key you have. The old style that has black case and no crome is easy to open. 

The new style with chrome sides and round panic button, is harder to open but it can be done. 

The newest key (current key) that has chrome and triangle for the panic button is a lot harder to open up. You will most likely damage the case. It may be wise to order a new case online. 

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