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Generalautotek, General auto repair
Category: Nissan
Satisfied Customers: 36
Experience:  Diagnosed and fixed over 1000 nissans in 20 + years
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I lost the only key to my 2000 Nissan Altima. I took it to

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I lost the only key to my 2000 Nissan Altima. I took it to a dealer who had a key made by a locksmith (not a factory key). The dealer then said he started the car, but was "unable to program the key." He told me wanted to remove the ECM and check out my wiring to see what the problem was. I told him nothing was wrong with my car when I brought it in and I suspected that he damaged the car by started it with an unprogrammed key. I had it towed to another dealer. That dealer said they performed a diagnostic (which they did not) and that I needed a new ECM. I bought a new ECM and the key still can not be programmed. The ECM is in "lock out." Nissan took a month to return calls back to the dealer and just said they don't know what to do. My question is: What damage can be done to the car by trying to start it with the wrong key?

Most cars with programmable keys, need a key (original factory) to program other keys. If the original is lost and none are available it may be possible for the dealer to clear out the programmed keys and start from scratch, maybe not. However you do need a factory type key, they are not usually cheap. If you had a New computer put in and a factory key, it is programmable. If you just have a plain metal key it will not work, there needs to be the "chip" inside the plastic handle and there is a programming sequence to follow.


Damage using the wrong key? Well the anti theft system goes into lockout as you described, however it should unlock after a period of time, or the dealer could unlock it (there has to be a way). It sounds to me like you just have the wrong type key.

Customer: replied 7 years ago.
I forgot to tell you. The second dealer got a real factory key. The key is no longer the issue. I have a new computer and a factory key and no one (we are now at a third dealer) can program the key. And Nissan can not give the dealer a solution.

(The key that the first dealer tried to start the car with did not even have a chip in it.)

Yes, that is a different story. I really don't understand why nissan cannot tell them what to do? How did the first dealer have the key made when there was no key? A locksmith could take the lock cylinder apart and going by the tumblers, make one. If they used the lock cylinder from the ignition switch something may have not been put back properly. Also, was the car trying to be started with the wrong key with the new ecm?




Customer: replied 7 years ago.
Aha! No the locksmith key was trying to be started with the old ecm. But you have a good point. I never thought about that. The locksmith could not make a key with a VIN number!

So what does this mean. The mechanics don't even know what to look at. The NEW ecm is still in lock out.

By the way, this has been going on since December 10 and I have made a complaint to Nissan USA and they dropped the case but won't tell me why, so I am so frustrated. I have no car and no one can fix it or get Nissan to return calls.

I want to know who did this, but most of all, I want a car. Arghhhh...

Now that I have more info I might be able to help, but understand I do not work for nissan, and there is no way in heck they should not be able to figure it out how to make it run again.


So I take it that the new ecm was trying to be started with a factory key, there is a programming sequence that must be followed for this to work. The first dealer should have been able to make a factory key with the vin# XXXXX proof of ownership.


If something was disturbed (and they somehow used the ignition lock cylinder to have a new key made) that could be the cause. The only other cause I can think of is possibly the Bcm (body control module) which might hold the key code as well as the pcm are not in agreement. A lot of cars use the bcm and the pcm to verify the key. I do not have my manuals in front of me now, I am at home and trying my best to help.




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