[instaclay]

I was also curious about this.

Maybe the keyless entry computer stays awake to try to sync with a fob and then sleeps on success? If a user chooses not to use a fob at all, maybe it stays awake indefinitely trying to find a key to sync with.

[blobbers]

Yeah sleep-wake problems often are related to things missing or broken in the (poorly constructed) system.

If the software on the car was poorly written, it may not have had a good back-off on the fob check, or if the fob itself was malfunctioning it may have left the car in a weird state.

While I wouldn't expect a fob to drain a car, it certainly doesn't seem implausible, especially given what the fix is.

[Captaffy]

From my own experience I believe the issue is that when these modules start to go bad they fail to turn off and stay awake indefinitely.