I tried the WD40 solution and it works. Great idea. I verified the side door was the problem by starting the vehicle and using a piece of wire to jumper the top and bottom switch contact on the frame of the side door. When I jumpered the contacts the light went off after about 1 second. This is a sure fire way to isolate the problem. If this stops working I'll take the side panel off and just jumper the contacts or maybe there is a way to jumper the contacts from the outside? Hopefully this will last for a while. Just bought a new Honda Accord. Sick of US engineered bullshit with this vehicle.

Okay , this is a real headache. I've read several of the comments posted by other members and have found some of the same underlying issues. I believe Ford should recall the vehicle. I'm having a problem with the "door ajar sensor". I suddenly started out of nowhere. One day I'm headed to DQ and when the kids and I got out of the van.... the lights never shut off. I went in hoping that the lights would shut off, unfortunately they didn't. Ten months later.... Still having the same problems... I've read some of the other comments and I think I will try the WD40 trick. I wonder if Ford has received enough complaints to RECALL!

Well I have had the light problem for years and we learned to live with it. I used WD40 and that worked a few times. Today the Ding Ding Ding started and would not stop. Couldn't live with that! I read the post on opening up the side door and came up with an easier approach. I drilled out the to rivets on the side door frame. This exposed the wire harness and it was a snap to cut the top and bottom wires and wire them together. 2 sheet metal screws later and that door was "closed" as far as the van was concerned. Problem NOT fixed. On to the rear door. I removed the inside door panel and found the wires that went to the side latches. Cut those BUT DO NOT WIRE THEM TOGETHER. You need to tape these wires off "open". Put it all back together and door # 2 "fixed". Still Ding Ding Ding and the lights are still on!!! Only 2 doors left. On to the driver's side door. After removing the panel I realized I could not isolate the wires for the latch. So I put it back together. Last ditch effort.... WD40 on the driver's side door latch. FIXED!!

I'm having the same problem with the door ajar switch that many of you are reporting - but unlike some of you, my problem comes with a nonstop SCREAMINGLY LOUD constant beeping sound. It is enough to make you want to jump out of a moving vehicle! My car will start beeping just as soon as the key goes into the ignition. Like another poster reported, if I accelerate FAST I can get it to stop temporarily, but I have to hit at least 30, and as soon as I slow down and the vehcile shifts down into 2nd or I apply the brakes - it starts again. I've also found that my problem seems to be temperature sensitive and goes away in the heat of the summer and starts as soon as the weather starts to change to cold - which I find is odd. I was reviewing the owner's manual instructions yesterday hoping for a solution and I decided to try to disable the tone alert that happens when you leave your turn signal on for over 1/2 mile since that is the same tone that is used for the door ajar sound. The manual tells you how to disable the turn signal warning by using the rear window defrost switch. It occured to me that there are only three tone alerts in the Windstar - for the lights on w/ keys in, the turn signal on too long and the doors ajar. I was unable to disable the tone alert from the signal. My rear defrost has been having sporatic problems - and I began to wonder if the tone alert was somehow linked to a short or fault of some kind in my wiring that connects with the rear defrost mechanism - which is why I can't always keep my rear defrost working and why I wasn't able to turn off the turn signal tone using the defrost switch as the manual suggests. Has anyone run into this problem? Meanwhile I'm going to try the WD40 which some of you have found helpful. If that doesn't work I'll bypass the switch in the sliding door. As far as the slider wiring is concerned, my locking mechanism in my slider began to fail about 2 years ago and the shop wanted almost $500 to fix it telling me that the motor that powers the auto-lock in the door was going out - so I opted not to fix it. (Hey the kids can pull up the lock and push it down like we did growing up, right? - for $500 they can, anyway!) Does anyone have any idea if this could be part of the problem? Have any of you who are having the door ajar problem also having problems with the lock on the slider or the rear defrost? With temperature? It is a shame in many ways that this is going on. The problem makes the car unbearable to drive when the tone is sounding - and I never know when it will start happening. I bought this car new and it has safely hauled my children and I around for 10 years now and I know it is a reliable vechicle - unless I go crazy from the beeping and jump from the moving vehicle!

I was also having a problem with my door sensors for the longest time. I thought for the longest time that it was the sliding door contact sensors on the exterior side of the door. In fact, it was not that. After I had replaced them and found out that was not the problem, I investigated it further, & come to find out that it was a rear contact switch located on the inside of the sliding door on the back of it. It may take a little time to take the interior door trim panel off to get to it, but it was worth it when i got it fixed, cause i no longer am having any more problems with the doors not locking or the interior lights not going off any more. You just have to be careful when you take the door panel off. The clips are plastic & will break easily, but you can buy replacement clips at an auto parts store fairly cheap. The part is also not that expensive, but you do have to purchase it at a Ford Dealership. If I remember it was about 20-30 dollars, but it was worth it though.

I too had an issue with the door ajar light staying on causing the interior lights to stay on. I took a previous posting idea and bypassed the switch in the sliding door. Here are the details: Remove the inner panel of the sliding door. This will take some effort, use a large flat screwdriver. Start from the left side as you face the door from the inside. Once you get the bottom loose it will come easier. Remove the door handle by removing the retaining clip with a small flat screwdriver. After removing the inner panel, you will see the four (4) wire harness on the inside of the door, to the left. It attatches to the four pins in the door that make contact when the door is closed. The two you want to isolate are the top and bottom pins. The top pin has a black wire, the bottom has a black with white line wire. Since it is nearly impossible to unplug the harness, ( the door handle mechanism blocks access) you can pull the wiring harness out. The other 2 wires go to the power door lock (if equipped). Expose the 2 black wires and cut them. Connect the black and black/white wires closest to the four pin harness (toward the left). Before you replace the panel, test the lights. The lights will come on when the door is open. Upon closing door, the lights should go out after a short delay. Ensure all other doors are shut. What you have done is bypass the door switch. This means the door ajar light is also disabled, so be careful. This repair costs you only time. It took me about 30 minutes to complete the task. Good luck.

We have had this door ajar and interior lights on issue for the last 4-5 years. We've had other electrical/computer problems too. We had the door ajar issue fixed once, but it came back. Our Service Engine light is on all the time, but since we get our engine serviced regularly and there is no obvious problem, we figure it's just the gas cap. Our anti-lock brakes started screeching and going in and out so we pulled the plug on the anti-lock brakes. Now our anti-lock brake light is on all the time, but the brakes work fine without it. Our newest problem is the door ajar light comes on and there is a terrible beeping noise whenever we brake. As soon as we accelerate, the beeping and lights turn off. This problem is REALLY driving us nuts. Have tried lubricating the door hinges and using steel wool on the sliding door contact points. This has worked only temporarily or not at all. Will definitely try the WD40 in the locks. If this works, I will be unbelievably grateful!

My door ajar light was on all the time. Then my dome light wouldn't shut off for about a half a mile. Then it wouldn't shut off at all! I even took out the fuse for the interior light #27 because I was afraid of running down the battery. Frustrated, I looked up the problem on another site... windstarguy.com and found the solution! Squirt WD40 in all the door lock access points, especially the overlooked rear lock of the sliding door. Then be patient! It took almost a full day for it to work. That evening I went out for milk but couldn't stand not having the power windows (which taking the fuse out will cause.) So I put the fuse back in.... the door ajar light went off and the interior lights were working once again! I'm so proud of myself I had to share this info with the other people with this anoying problem