Charlie Sheen's car that went over a cliff this morning on Mulholland Drive was ready to drive ... because law enforcement tells us the key was in the ignition and the garage door at his home was open.


Charlie lives in a gated community where other residents sometimes leave their garage door open as well.

Our law enforcement sources say when they arrived at Charlie's home he looked fine and told cops he had no idea who heisted his ride.

Cops say other cars in the gated community were burglarized.