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Electronic keyfob questions.

Hi All,

2003 Transit Connect. Comes with a 'chipped' Tibbe key and a separate 3 button keyfob.

We have bought more keyfobs and programmed them to the van using the ignition key process and all (3 more and original) worked first time.

We have had a Tibbe key cut from a picture of the key and that works fine (and now we have the Tibbe code for our records).

Apparently, with two *different* chipped keys (keys with different codes) you can then program the van to accept additional (different) key (transponder) codes and whilst the owners handbook suggests you can also clear any additional transponder codes stored (with the two 'different' keys) that process either doesn't work or isn't guaranteed. A 'cloned' key would just work of course.

Now, I think I understand there are two (or more?) types of suitable transponders. One type are blank, or partly blank (there may be a fixed / unique component, like the vendor code on a MAC address vendor ID?) and would be used when say a locksmith is 'copying' a key. The other type is fully programmed with a *similar* code / format to our existing key(s)[1] and therefore, as long as our two existing keys

*are* different, the van could be programmed to accept this third (and equally different) key-transponder (max 4 or 8)?

I'm asking all this because my local high street Locksmith didn't seem to agree, suggesting that all our keys would have the same code (and whilst they could have, if they we are all clones of each other or another possibly now lost key) they wouldn't be identical from the factory (or you wouldn't be able to use the d-i-y two-key programming technique).

Before buying and trying to program an additional transponder into the system, I'd like to find out if the two existing key / transponders we already have unique codes.

So I'm really looking for confirmation that my understanding is correct or explanation of why it isn't please?

Cheers, T i m

[1] I don't know if the same chip type may carry different vendor codes when used with different vehicle marques etc.
Reply to
T i m
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The chips are made by a small number of companies. The code would have a header for the car manufacturer and model, and the last part is the rolling code. Some cars recognise different keys, in order to personalise the settings (rear view mirror angle for example). I don`t know if your Transit would. Otherwise the keys are the same - just the rolling code would be at a different point in the cycle. So if a spare key is unused for a long time, it may need to be synchronised with the car again, as a window of 255 codes is checked each time.

Reply to
mbjorn

I'm not sure what you are asking but when I had my bike with an S4 alarm system while the keys would all work they were treated sequencely by the alarm system. I.e the keys were electronically numbered 1 2 3 4 etc.

Reply to
Norman Rowing

Ok.

I thought that might be the case.

So do all cars using any chip employ the 'rolling key' system can you confirm please? ie, is there a chance this 2003 van doesn't?

I can only suggest it does because (according to the owners handbook) for the owner to program the system to accept additional keys you need at least two 'different' keys that are already accepted by the system.

Or not, if the system in question doesn't employ the 'rolling code' system (I'm asking / suggesting)?

The reason this is of interest to me is that I'm looking for the cheapest way to get a spare key for our van. We already have a spare mechanical key (cut to code) and in theory, if we could get 'a different but compatible' chip we could, assuming the two existing keys are 'different', program the system to accept the third.

Now (if my thinking is correct), that chip could be a straight copy of any other similar vehicle as I could put it into our spare mechanical key and then simply program it into the system. The owner of the 'donor chip code' wouldn't also have the right mechanical key so the chances of that process creating a security risk being very low?

Or I could source any other 'generic' chip correctly pre-coded in the right format as it is unlikely it would be the same total code as either of the existing ones?

Or am I miles off? ;-(

Cheers, T i m

Reply to
T i m

Yes, I think this is the same with this Connect, with (I believe) 8 'slots' that would each be paired with 8 'different coded' keys.

So, with two different keys the system allows the user to add additional keys (max 8). They are also supposed to erase all keys (slots?) outside the two used to initiate the purging sequence (although it has been suggested that this second process doesn't always work as it is supposed).

If I can source a generic chip, pre coded in whatever format is required by the system, I could be able to program the system to accept it (assuming the two existing keys carry different codes).

Cheers, T i m

Reply to
T i m

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