2003 E500 Keyless Go module upgrade?
I bought my 2003 E500 used and it has the Keyless Go feature. It came with one key fob that I can use to unlock the car and start it normally. When I try to use the Start/Stop button on the shifter, I get "Key not recognized". This message also appears with every pull of an outside door handle, push of an outside door lock button, and push of the trunk unlock button. I guess this means the Keyless Go system is working and trying to get a response from a KG-enabled key or card.
From my research I believe the 2003 only used a KG card and not a KG fob. However, I would expect "Key not detected" instead of "Key not recognized". Do I just need to have my current key fob "programmed" as a valid KG key?
I also tried to order a KG card. I've asked a couple of dealers and was told the card is no longer available for the 2003 model year. As a last resort, I'm thinking of replacing the KG module with one from a later model year, purchase a compatible KG key, and then have it programmed.
Do I have to replace ALL KG modules (rear module, interior module, left rear door, right rear door, as well as antennas)? Or do I just need to replace the main/rear KG module? I also wonder if a previous owner already did the KG module swap and that is why I get the "Key not recognized" instead of "Key not detected".
Thanks,
RC
.
My key doesn't have a visible number. It's the only key that came with the car when I bought it used so it's likely not a KG key. There are no Keyless-Go related codes so I think I have to get a new KG key. But two dealerships (in the Phoenix area) said they cannot get KG keys for a 2003 model year. Will MY2004+ Keyless Go keys work with this system?
Thanks again,
RC
Last edited by konigstiger; Dec 7, 2020 at 01:15 PM.
One more question: Is this something I will have to have the dealer program?
Thank you!


