Car stops all systems freeze and dash displays 'key'

[joyceM35]

Last night i turned on the headlights and they did not come on. I then started the car and same thing. A few seconds later they came on.
The next morning my wife was 10 houses down the road when the dash lights went out and the car rolled to a stop. The dash said 'key'. The headlights were on and could not be turned off. No electrical systems would work: seats, trunk, locks...
I tried a second key, no change.
I disconnected the battery for 5 minutes then reconnected it. The headlights were now off, but no other change. It was this way for 2 hours until the tow truck arrived and took it away.
Two hours later at the dealer, it started right up and they say that they can find nothing wrong.

Needless to say, i am concerned that this could happen on the interstate. I can not see keeping the car if they can not find the problem and fix it.

Car never had problems before 2007 M35 40k miles. No recent work. Under Infiniti warranty.
Any ideas will be appreciated.

[Ace2cool]

Dealers are great at "not finding anything wrong." I'd think there was something wrong with the key receiver, and it lost connection while driving, and once they loaded it onto the tow truck and bounced it around, it was able to reconnect.

However, if the seats wouldn't even work, that indicative of total power failure in the vehicle, because I believe seats are constant powered items, aren't they? (Don't know, I don't own an M35, but they are on my Z)

If they are only powered with aux power or ignition power, then my first statement stands.

Does the M35 have the little "slot" in which to put the key in case of the key battery dying, like the altima does? I would have liked to see what it would do if the key was inserted.

[The00Dustin]

To be clear, the "Key" light came on, as opposed to the LCD saying "No Key", correct? I don't know how to help you, but such clarity might help someone else. They "Key" light was always on when I bought my 06 M45, and I am colorblind, so I thought it was a normal green light until someone asked me about it. The dealer replaced the key control unit or something under warranty as they described it as a safety issue. Maybe if you clarify to your dealer where what light was they will investigate a different way and find the issue?

[joyceM35]

We had tried everything with two keys and no effect- As for the seats, they are always powered(except during the problem). The dealer kept the car for 4 days and let the mechanic drive it home- no problems. They determined that the most likely problem would be some sort of steering column sensor, possibly related to the key; so they replaced it. We have been driving the car for a week now and have not had any problems...yet. Hopefully they got it right. I am continuing to drive the car as much as possible so that if it happens again, it will be with me rather than my wife...