Hello all! I’m looking at picking up another G35 coupe today. I want it for a project but have some concerns. It’s listed as having a new engine and transmission. He says it runs but needs a key reprogrammed. The story is that the drivetrain came from another car that was wrecked. But now there’s no communication from the key to the ECM. Or so I’m told....The seller states that it’s a simple as towing a car to a mechanic or the dealership to have a key reprogrammed. Or program to the car rather. But in just a little bit of investigation, it sounds like it may be more involved than that. Does anyone have any experience with this? If the car was cheaper, I would buy it for a shell. But for the price he’s asking I would like it to run

 

Swapping the engine does not have ANYTHING to do with the NATS security system (which handles the key RFID codes). However these cars are prone to having a heart attack and forgetting the key programming especially if you leave the battery disconnected for a long time.

Call around to local locksmiths, many of them are able to reprogram the key from a handheld tool so they can drive to the car, program the key, you drive off.

This way you're only out $100 or so if the key cannot be programmed and it turns out to be something more major like a fried BCM or ECM.

However I'm VERY doubtful about this being the issue because if the key programming was lost then the car WOULD NOT START. You said the seller description is that the car runs? Is it one of the intelligent fob systems (keyless start) and the fob died so it's being started "manually" by holding the fob to the key slot? If that's the case then yeah it's likely either the fob died or the BCM lost the programming and I would buy it because that's a minor issue.

There are two types of intelligent key systems that were available, the earlier version (2005 I think) the start button was actually a **** you turn on the steering column. This system has VERY expensive fobs since there weren't many cars equipped with it. The second system that I think was 2006+ used a push button on the dash to start, it's fobs are much less expensive.

Both use the same system to program it, either a locksmith with the correct tool or the dealership Consult-II tool which they charge 1 hour of labor for.

 

My 2006 coupe AT has the intelligent key twist-to-start on the steering column; no pushbutton. There is an emergency key in the fob that you can use to unlock the door and start the car (by interting into the twist key receptacle) if your fob battery croaks for some reason.