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Seat Belt Warning Light

5175 Views 11 Replies 4 Participants Last post by  Mark_Hone
I am looking for a new, used but functional, or replacement part for the Seat Belt Warning Light Relay part no.C6AB-10B924-C (Tung-Sol Relay #673) for a 1966 Mustang Convertible.
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If you find two, let me know. They're tough to find.

Watch at swap meets for C7AZ-10B924-B1 this is the replacement for the orginal canister type. If it's still in the box it's marked switch which throws alot of people off. You might want to open the canister on yours and see if it can be repaired. I've repaired a couple in the past because the resistive wire burnt open close to the terminals making for an easy repair. Good luck.
Service Part No. is C6AZ 10B924-A.

You might find one -here-
I purchased one not too long back from
How do you know if you need a new relay? Since I discovered and replaced this mysterious light bulb under my dash (bezel and lens missing), it comes on only when my engine is running and never shuts off unless the I turn the car off. Is this light supposed to shut off when seat belts are engaged or after a time period?
It's a relay.... if working, it should come on for ~7 seconds when you first apply switchable power the the vehicle. It's not actually connected in any way to the seat belts.

The vast majority of cars have burned out relays that don't come on at all.

The part that you are looking for is almost impossible to find (trust me). However a replacement part can be used. It's from a late model ford truck or aerostar van. The part # is: SW-1822 and also on the outside of the box is the # E4TZ-10B924-A. The switch inside has a different # on it: E43B-10B924-AB. I dont know why the different numbers, but there you go. If you get one, the wiring hook-up is easy, but too long to explain here. P.M. me if you want, and I will "talk" you through it. Mark
Yes, that's what this relay that I'm looking for does. I took my old one apart when I determined that it didn't work and found that this relay is designed with disimilar metal contact bars one of which is wrapped with a filament wire that is grounded so that when you turn the car on the filament wire heats one of the contact bars causing it to break contact and turn the light off. Consequently, this relay glows red hot all the time the car is running thereby keeping the contact broken and when you turn the car off the heated bar cools and reconnects making contact with the other bar. Repair of this relay would be a delicate operation as the filament wire is very fine.
I got mine from Perogie Enterprises. Expensive little bugger!!

OK Mark,

I purchased the module as you described.

Now to hook it up.

The module has 7 blade connectors coming out of it (4 in one row and 3 in the other)and the plug on my mustang has 2 slots. Ground was achieved in the original relay through the case so that when you bolted it to the car frame it was grounded. In looking at the blades on the new module I think I can figure out which one is ground. All I really need to know is which 2 of the remaining 6 do I need to connect up too??

For ease of explanation let's say that we are looking at the connector end of the new module with the 4 blades on top and the 3 blades below. That would mean that the ground blade is in number 1 position on the second (3 blade) row.

Please take it from there.

Thanks in advance.

Dave Tostenson
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Dave: If you hold the new switch facing you with the 4 blades on top, the top right one is the ground (you must make a short (3-4") ground wire to attach to this blade and then to a ground (pedal support or near by). The next blade to the left, goes to the light, and the next blade to the left goes to the live feed (ignition). So, you are using three blades on the top, and not using the first blade (far left)on the top. The three on the bottom do not get used at all. I hope you can make sence of this, but if you can not please e-mail me and I will try to do better. Good luck. Mark
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