Jim Grant's Tech Tips
96 Mercury Sable, Lights Wonít Turn Off
Hi Jim, I have a Ď96 Mercury Sable with a 3.0 engine. The problem Iím having is the interior lights stay on when the doors are closed. It only does it now and then. Can you help me?
- Dean Defrancesco
The problem youíre having is a common event with Ford and Mercury vehicles, including their light trucks. The most common cause we find is a sticking switch in the door latch mechanism. The switch is not too hard to replace after you get the inside door panel off. But, it can be a little tricky knowing which switch is bad. Why is that? Each door and rear gate or hatch, if a wagon or van, has a switch on the latch. If youíre the only one in the vehicle when the condition occurs it is likely, that the driverís door switch is the sticking switch. If many people get in and out of the vehicle, it becomes more difficult to determine which switch is the cause. In the shop we have a computer scan tool that makes that job a lot easier. How is that? The interior lights, along with many other accessories, are computer controlled, the switch just serves as an input of information. The body computer takes that information to turn on the lights. A good computer scan tool just happens to have the software that allows a technician to see just what the computer is seeing. It is even likely that there will be a code in memory for the door switch. Just like most driverís, the computer is smart enough to know that the door shouldnít be open while the vehicle is moving, resulting in a code being set. So, in watching how and when the problem occurs may point out just which door switch is the problem. If not, just ask the computer. It doesnít want you driving with the doors open either.