Mercedes key rom swap?

[mgrharry]

Got a customer who slammed their Mercedes key in the door and broke part of the tip. They are inquiring about buying a used key and swapping the ROM chip. I've got a hot air station so it should be pretty straightforward. But which one is ROM? Photos attached below.

[stj]

Re: Mercedes key rom swap?

it's not that simple,
there is an rfid that is used for the immobiliser, and a battery powered transponder that is coded to the car too and used for the button functions AND to store a backup of the mileage in the key!!!

you dont need to swap chips, you need a mercedes "star" diagnostic setup with a key interface.
mercedes use the most complex keys around - it's not like a ford.

btw, next time take pictures big enough to read the chip numbers - atleast 5 times larger than those..

[mgrharry]

Re: Mercedes key rom swap?

Here are some zooms of the chips if it helps. But you're saying even if ROM is swapped it's a no go without the diagnostic programmer?

[Aussie Max]

Re: Mercedes key rom swap?

He's correct looking at your photos, the PCB has broken tracks. You could try to link the broken tracks (with links initially) to see if it works. If so do fine links and lightly cover the board with rapid fix (there is no other force on this board.

I've done it with success

Graeme

[mgrharry]

Re: Mercedes key rom swap?

Here are some higher rez photos

[stj]

Re: Mercedes key rom swap?

i suspect the broken "coil" is the rfi transponder and contains the chip in the center.

[mgrharry]

Re: Mercedes key rom swap?

Doh! So... lost cause it seems.