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Old 29th January 2016, 06:54   #4
marinabrian
 
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If you attempt to copy a key transponder to the EWS, yes it can be done.......however the EWS will see this as a data mismatch as the VIN is locked in the transponder thus making the transponder useless.

The PCF7930AS has the security fuse blown after programming, meaning it cannot be overwritten with new data from another EWS, again meaning used transponders cannot be reused.

Brian

Quote:
Originally Posted by genpk View Post
Just as a matter of interest Ive been playing around with my EWS Editor Lite program to see what it can and cant do while waiting for some new key chips to arrive and as I had a spare EWS module, thought id see if you can code existing old keys from other Rover 75 cars to the EWS.
Info says it can be done..
I had a coupple of old Rover 75 keys so tried it out and found a couple of interesting things,the program definately reads the old keys and it will code the old key to the EWS -EXCEPT it seems to always want to take key position 00 and will replace the key that is already listed on the EWS at 00.
Unfortunately key 00 is usually the active one but this is fine if you have no key or your one key you have is listed at 01 or 02 but in my case,the one working key was listed at 00 so it would have been pointless to do it.
Pain in the a...se as no matter what even if I tagged the key as 03 or whatever number,the key data would then change to the data that already existed for the key listed in the EWS at position 03.
Suppose its fine for a car with no keys but seems you need blank chips to take up the spare key data (KEYS 3 TO 9 )from the EWS.
At least you can use the circuit board in the old keys.

additional info - seems the original transponder chips ,PCF7930 are not a re writeable chip ,once coded thats it. ,the current chip to use appears to be a PCF7935.
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