Cinquecentos first:
L and M reg - These cars do not have the built in keycode immobilisers and use black keys.
M to S reg - These cars DO have the immobiliser built in, and should come with a full compliment of ONE red and TWO blue keys. The red key is the master which is needed for Fiat to make new blues up, or for certain work involving the ecu and immobiliser. This key shouldn't be used as your day to day key, but should be kept in a safe place. Blues can be 'cloned' though - i.e some places can make a new blue key by copying an existing blue one - search the internet for 'Transponder keys' for more info. If buying a car without the red key, haggle the price down accordingly as if the worst did happen, you could end up needing a new ecu,code box and a full set of locks(or ignition if your happy using different keys to lock/start). That can be big bucks, even if using parts from a breakers.
however nowadays new keys can be 'cloned' from the blue key at places like timpsons.
if you have a CODE 2 set up then its a dealer only job to get keys im afraid.at time of writing this is around £140 for 1 key supplied and coded.so haggle if you only get one key on a car!
A rough guide on how to tell if your cinq should have the red/blue keys - Phase one cars have a crease across the boot lid at about the level of the top of the rear lights. If yours has the crease, chances are it's not got the immobiliser built in and will have the black keys.
Seicentos:
1998 to 2000 approx :
Red/Blue key setup as above.
approx. 2000 on:
Different type of immobiliser keys. No separate red Master key supplied, just 2 ignition keys with built in chip. Much less hassle!
for the picture below:
The left key is a Code 1 Red/Brown
The middle key is an old style code 2 key
The right is a new style code 2 key

in this picture you can see the small transponder in the key casing

If the key has a transponder sign on it (Triangle with 2 little rings around the top) then it needs a master key. If it has a 2 on it, its a 2nd generation one and doesnt. If it has nothing then it dont need one either, according to Peter, chairman of FMCGB!
Thanks to thanks to pete(fixitagaintommorow),Centoevo and Alfanige for the Sei info and POWL for the picture
L and M reg - These cars do not have the built in keycode immobilisers and use black keys.
M to S reg - These cars DO have the immobiliser built in, and should come with a full compliment of ONE red and TWO blue keys. The red key is the master which is needed for Fiat to make new blues up, or for certain work involving the ecu and immobiliser. This key shouldn't be used as your day to day key, but should be kept in a safe place. Blues can be 'cloned' though - i.e some places can make a new blue key by copying an existing blue one - search the internet for 'Transponder keys' for more info. If buying a car without the red key, haggle the price down accordingly as if the worst did happen, you could end up needing a new ecu,code box and a full set of locks(or ignition if your happy using different keys to lock/start). That can be big bucks, even if using parts from a breakers.
however nowadays new keys can be 'cloned' from the blue key at places like timpsons.
if you have a CODE 2 set up then its a dealer only job to get keys im afraid.at time of writing this is around £140 for 1 key supplied and coded.so haggle if you only get one key on a car!
A rough guide on how to tell if your cinq should have the red/blue keys - Phase one cars have a crease across the boot lid at about the level of the top of the rear lights. If yours has the crease, chances are it's not got the immobiliser built in and will have the black keys.
Seicentos:
1998 to 2000 approx :
Red/Blue key setup as above.
approx. 2000 on:
Different type of immobiliser keys. No separate red Master key supplied, just 2 ignition keys with built in chip. Much less hassle!
for the picture below:
The left key is a Code 1 Red/Brown
The middle key is an old style code 2 key
The right is a new style code 2 key

in this picture you can see the small transponder in the key casing

If the key has a transponder sign on it (Triangle with 2 little rings around the top) then it needs a master key. If it has a 2 on it, its a 2nd generation one and doesnt. If it has nothing then it dont need one either, according to Peter, chairman of FMCGB!
Thanks to thanks to pete(fixitagaintommorow),Centoevo and Alfanige for the Sei info and POWL for the picture
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