Jim Grant's Tech Tips

'99 Nissan Maxima, Replacement Key Programming

Q: I have a '99 Nissan Maxima and I lost the ignition key and have no
other. I ordered one from the dealer and now they tell me I have to
bring the car in to program the key. Can you help me with the
procedure to do this.

R.J.

A: As the vehicle owner there is nothing you can do yourself to program the anti-theft system (in your case Nissan's Immobilizer system). The ignition key in your vehicle, and like most vehicles made today, has a 2-part security system. The first part is pretty standard, all those little bumps and grooves, which is a mechanical coding, that has to match up to the coding inside of the ignition switch or it cannot be turned to start the car, much the same as a door key that you would use to a house or apartment. The second part is an electronic code system. The ignition key has an imprinted code that is transmitted to the security system of your vehicle when the key is placed into the ignition switch. This part of the system is the electronic version of the bumps and grooves that you see on the key. The security system which really doesn't care much about the key fitting the switch, is looking for that piece of electronic data that says yes I know this key and I will allow the engine to start and run. The next thought that people have is to pull the security box out of the vehicle, problem solved. Sorry it's not that simple. The security system is networked with the engine computer. Guess what the engine computer is looking for? That's right, an electronic code from the security system. To solve your problem you'll need to have the vehicle towed to the dealership to have the key and the security system recoded/matched-up. As you mentioned early you ordered a key, as in only one. I would suggest buying 2 keys and having them coded at the same time. If you don't, and buy a second key at a later date you'll have to return to the dealership for recoding of the car's security system and both keys. Doesn't technology just rock!