What could cause LH-F door open warning on a range rover p38 when door are closed?

Answer 1

Several things are possible. The drivers side door is opened and closed more than any other. In that door is an all in one electrical door lock actuator. It locks and unlocks the door using the key fob. One of the electrical circuits in that device detects if the door is open or closed. That circuit is fed by a cheap plastic part internally that gets bent/warped over time. The open door error typically happens more often when the car has been sitting in the heat. The correct fix is to replace that door lock mechanism. (not cheap, couple hundred for the part along not counting the labor to remove the inner door panel to get at it.) The cheap and dirty way is to pull the rubber seal where the wiring comes from the door into the car body. The blue wire is the one that feeds the door open message. You can jumper that wire to the black wire and the door will think it is closed. That fix means the door will ALWAYS think it is closed. Locks work etc. but opening that door will not turn on the interior light anymore. The right fix is take it to the dealer and pay them the $500.00 to fix it.