seat belt warning light stays on w/ parking lights on

[69_vert 5]

Hi All-

 

New to this forum. Rebuilding my 1969 convertible (original and new pics of car shown) and putting the dash together. I have been testing things to make sure I dont get the dash together and then find a problem.... I know very rare... for most of us.

 

My problem is that the seat belt warning light stays on when I put the light switch in the parking light position. It doesnt go on when I put the lights on, or when the car starts. I have looked at some of the previous threads here, and am wondering whether this particular gremlin would occur if the bimetallic switch (which i cant seem to find) was not grounded properly.

 

All the other lights seem to work properly, but clearly, they are working despite my prowess!

 

Any thoughts about how to troubleshoot this would be helpful.

Thanks

 

 

 

 

[SA69mach 39]

Remove the sending unit and test it with a simple 12V test light and a car battery.

 

Clean the ground and the metal tab as rust could be causing a failed ground.

 

Let me back up a bit.  Do you have the SBWL in the instrument panel, or the type that is fitted into the dashboard (just below the ignition switch?

 

The warning light wiring is not connected to the light switch.  I would be interested to see the wiring if you can trace it.   it should be a single wire from a 'key on' source to the unit, which is screwed to, and grounded on the dashboard metal chassis,  and from there- one wire to the bulb socket (which should be in the instrument panel).

[69_vert 5]

Hey thanks SS..

 

It is a standard dash with the bulb plugged into the instrument panel. I will try and trace the wire back. It makes sense that it wouldnt be on the light switch... so I am wondering where it could be. I actually don't see the switch itself, which is also curious. should be a quiet afternoon under my dash...

 

cheers

[69_vert 5]

Hey SS-

 

Since I cant find the switch I did a bit of digging. Can you or someone tell me whether the light above igniition switch turns on when you have the parking lights on. It has a black and yellow one lead wire. It could be the same size as the seatbelt warning light-- the electrical figure is highlighted here.

 

 

[Midlife 814]

That's the correct color wire for the ignition switch lamp. 

 

The seat belt lamp system is fairly simple: there's a relay that runs for just a few seconds after power is applied.  Power is applied to one side of the lamp and ground is the other side.  I'm willing to bet someone previously screwed with the wiring.

[69RavenConv 286]

Can you or someone tell me whether the light above igniition switch turns on when you have the parking lights on. It has a black and yellow one lead wire. It could be the same size as the seatbelt warning light-- the electrical figure is highlighted here.

 

Yes, that's the normal operation of the ignition switch light - on with parking lights, off otherwise. Agree with Midlife, someone's messed it up for you. Nice looking vert, BTW.

[RPM 1,190]

Welcome to the forum 69_vert!

 

On a thread related note, why did some cars get the seat belt warning light and others didn't?

 

Very nice looking 69. From your pics it looks to me like you may have recently replaced your bumpers. If so , from whom did you get them and do you like the fit and finish?

[Raven R code 281]

could you post a picture of the belts warning light? I am missing mine and want to see what yours is like.

I've seen another one from a member and want to see it they are all alike.

 

thanks,

Dave

[69RavenConv 286]

On a thread related note, why did some cars get the seat belt warning light and others didn't?

 

I think it was coupled with deluxe seat belts. Tach cars got a jewel light by the ignition switch (pretty rare), all others had the light in the cluster. This is based on hazy memories of gossip I've heard over the years, so I could be wrong.

[SA69mach 39]

The information above, about the variations of the seatbelt light are correct.  The tach cars had no provision in the instrument cluster for the bulb and red lens, so those cars got the round bulb attached to the lower dashboard.  They all essentially work the same.

 

As your car is non tach you should have a round hole for a press-in bulb socket in the cluster, with a red lens printed with the text "SEAT BELTS"  I am going to assume you do not have the 'relay' and the wiring.  Looks as though your PO simply slugged in the wrong bulb into that socket(which apparently should be plugged into the ignition switch illumination hole in your car)

 

I am having trouble linking and attaching anything last couple of days, but if you do a Bing or Google search for 'Mustang seat belt warning light relay' you will see plenty of images of the small metal unit and the simple wiring.

 

Both my 70 and later, my 69 Mach1 did not have the relay or wiring in place either.  I made one from scratch for the 70, and purchased a complete set off ebay for the 69 Mach1.

 

Please advise if you want details of how to make yours, or if you are just going to search for an original.  Be sure your unit/relay has the 'tang' intact.  That is the tab which is screwed onto the chassis, under the dash near the steering column.  It is the ground for the entire array, and is essential to make the light work properly - I only say this because some I have seen advertised have the tab broken off.  I don't think any sort of welding or brazing will be good for the internals - but I am not sure of that to be honest.

 

Don't get too hung up on what exact year or make for the relay - if it is the same shape, it will work.  Autolite made them, then Motorcraft, and also Tung Sol made them.  All identical.  Just get the cheapest ones you can find.  The wiring is a piece of cake.

 

One last thing,  Super Stanger is not my 'name', it is just a tag like 'Senior Member' or "newbie" that is generated by the site, or admin??  I post here under SA60mach.  I don't care either way, just sayin....

[69RavenConv 286]

One last thing,  Super Stanger is not my 'name', it is just a tag like 'Senior Member' or "newbie" that is generated by the site, or admin??  I post here under SA60mach.  I don't care either way, just sayin....

 

If you click on your handle at the top right of the page, then select "My Profile", the click "Edit my Profile", you should be able to enter anything you want for "Member Title" (including blank). The switch over to the new forum software a while back introduced many gremlins :)

[RPM 1,190]

Hmm...that Super Stanger name has a nice ring to it.

 

Good info here guys, thanks.

[69_vert 5]

hey guys

 

Thanks for the info. Looks like nothing in the wiring was hacked, just had the ignition light stuck in the seatbelt warning bung on the instrument panel. So thats a positive.  As for the warning lights for the seatbelts, I will opt not to put them in.  I can do without that light for now. The important part is that there are no loose dangling broken wires to short out (knoc on wood).

 

As for the bumpers, I did not replace them, and they look pretty good. But I dont know if they are repops or not.

 

SA60 thanks for the correction.. I can be referred to as dumb*** newbie!

 

I will have more questions as I try to finish off this rebuild.

 

cheers

D A N!