So I changed the ECU in my car and had to have new keys cut.

The ECU is a used one from a totalled car.

The keys were cut but hasn't been programmed.

The car has the NATS system.

I took it to Nissan several times but they haven't been able to program it. One of the times I took it to Nissan, the master tech guy said the Immobilzer ring around the ignition was the last issue, so I changed it.

The last time I took it to Nissan, the master tech guy was on vacation but they let one of the other tech guys try but he only knew how to program keys. So when he attempted to program the keys it failed.

He admitted he wasn't as familar with using the Consult II like the master tech and said he might not of been able to program the keys because the ECU was not programmed (something he didnt know how to do).

The security light blinks with the key off but goes solid with the key in the on position. It cranks but doesn't start.

My question(s) are:

1) In order for Nissan to program my keys, will the have to program the ECU first?

2) If they are able to program the keys without programming the ECU, does that mean I could just have a locksmith with the ability to program the keys to it instead?