Seat Belt Light Stays On 1989 T-Bird


Oct 28, 2023
Vehicle Details
1989 Ford Thunderbird Base 3.8L
Hello everyone, I am new. About 2 months ago, I bought a 1989 Thunderbird Base 3.8L with 46,000 miles. Love the car--very comfortable, nice looking, easy to drive. Its nice to drive a car that you just don't see very often anymore. I also have a 2011 Mercury Grand Marquis as my daily, though I've been using the Thunderbird pretty frequently as well. I really like the older cars.

I have a question about the seat belt light on the instrument panel. It stays illuminated even if my seat belts are on. The only way the light will go off is if both the driver's and passenger's shoulder belts are clicked in. The lap belts, it seems, have nothing to do with the light. Has this happened to anyone else--how can I fix this? Sounds like maybe a dirty sensor? I don't know where it would be though. Is this how it is supposed to work?? I don't know I have never driven this car before. I would appreciate any input or thoughts, thank you kindly.
Wait, so you have the shoulder belt unplugged on the passenger side? If so, then that is your problem. That belt should stay plugged in all the time, and the motor will move it forward when the passenger door is opened, then back when the door is closed and the key is turned on.
So in order for the seat belt light on the instrument panel to go off, both driver's and passenger's shoulder belts must be clicked in? If so, is there something I can alter so the that the light will go out if just the driver's belt is clicked in, or maybe for the light to go out completely?
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Again, why? The shoulder belt is meant to remain plugged in, and then the automatic belt mechanism moves forward when the door is opened to allow you to get in or out. Really there’s no reason to ever unplug it, let alone drive around with it unplugged.
Just buckle the shoulder harness into the automatic retractor.

If for some unknown reason you don't want to do that, remove the bulb from the cluster if you want the light to go out.
Okay, I understand what you're both saying. I've never driven a car with the retractable belts. Now that I think about it, it does make more sense to do that with the shoulder belts. I appreciate everyone's input, thanks.

Just out of curiosity, does anyone know where is the sensor for the seat belt light?
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Depending on the vehicle, there might be several sensors related to seat belts, not just to illuminate the seat belt light but to tell the airbag system when or when not to deploy. Based on the vehicles in which I have replaced the carpet and not knowing the belt configuration of your '89 (you don't have safety belts but separate lap belts and shoulder belts?) I'm guessing that there is a sensor/switch in the buckle with an electrical wire leading to a connector near where the belt assembly bolts to the body of the car.
There is also a sensor in the door itself. I know if it goes bad the belt no longer is automatic. They went bad in mine, didn't feel like changing them so I unplugged them so the door adjar light stays off and they stay all the way back. I was going to change the sensor but got used to just flipping the belt over once I sit down and honestly preferred that versus hearing and seeing the belts go forward every time I open the door.
Okay I see, interesting. Thank you, I appreciate everyone's input.

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