Seatbelt warning light comes on with headlights .

[cwerve]

I am restoring a 74BB manual transmission convertible. I am down to the last of the little things that are wrong. When I turn on the headlights the seatbelt warning light comes on. This is the year of the no start seatbelt interlock. The seat belt light seems to work correctly with the headlights off. The no start interlock seems to work correctly. Did some searches and found another with the same issue on a 74 but they had no resolution. Maybe this is a know problem with an easy fix. The other warning lights seem ok like the headlight door not open & door ajar.

Is there a buzzer for the headlights on and engine off? If so it is not making any noise. The seatbelt buzzer is working.

Any help or guidance would be appreciated.

 

[bill81vette]

sounds like your headlight switch is also powering the seat belt lite as well.
crossed connection?

 

[Vettehead Mikey]

When I turn on the headlights the seatbelt warning light comes on. .

Does the headlight warning lamp come on at any time? Has someone been behind that dash and put the wrong lamp in the wrong hole?

 

[cwerve]

OK that sounds like an easy fix.

Question on clarification-- Seat belt buzzer and seat belt light--should they both come on and off at the same time?

What I have (1) Key on passenger sits down buzzer come on, connect belt buzzer goes off. or(2) passenger belt closed then passenger sits down buzzer come on. Both of those sequences seem correct but the seat belt light stays off. That seems wrong. along with seat belt light come on with head lights.

Wrong bulb in socket might be a good place to start. Of course that begs the question where is the seatbelt light ? Lets start with what is the proper logical sequence for the light to come on & off.

 

[cwerve]

Update: got out the wiring diagram. Looks like the seatbelt buzzer and light should activated at same time. Also if E-brake is on the buzzer and light should be off. So armed with that info I am getting out the screwdriver and test light kit and going in to see what I can tear up.

 

[cwerve]

Folloow up and solution

It took a bit of time but the seat belt light mystery is solved. Vettehead Mikey hit it on the head. The lights were swapped. Seat belt warning and dash light. I had not taken the center console out to investigate but had I, it would have been clear. The dash lights all have gray wires and the warning light has one yellow and one yellow with a stripe. The additional clue came from my 4 year old grand daughter. It was early evening and we went for a ride. Upon returning she unbuckled before I had shut down. Too my surprise I saw light coming from under the dash each time she bounced on the seat in time with the seat belt buzzer. Her exuberance from taking a ride in a 74 big block convertible caused lots of jumping up and down on the seat in the driveway. So I dove in and took apart the dash discovered the light swap and also fixed the clock while I was in there. Thanks for all the help greatly appreciated.

 

[Vettehead Mikey]

Glad to hear that the mystery is solved and for getting back to us!