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TR6 74 TR6 "seatbelt module"

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poolboy

poolboy

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74 TR6 "seatbelt module"

So do you think I will mess anything up by unpluging the multi pronged electric plug from the buzzer module?
The reason I ask is because as most electrical problems do, my ignition key failed to get the starter to engage.
Troubleshooting began with a check of the solenoid. OK.
Fuse. OK. No voltage in the W/R wire at the starter relay.
Studied the wiring schematic. Took the weather cover off the starter relay and engaged the points with my finger and the key in the on position. The engine starts!. You know what a pain it is to deal with the ignition switch; so I tried one more thing.
From looking at the schematic it seemed like the White/ Orange wire from the "seatbelt module" must be hot when the key is turned to START; mine wasn't. So I jumped 12v from the battery to the W/O terminal of the starter relay and BAM, Ol' Basil fired up.
That's where the "seatbelt module" comes in. I made a jumper from the W/R terminal to the adjacent W/O terminal on the seatbelt module plug, turned the key to START and again the starter spun and the engine started right up.
Since I had unplugged the plug to the buzzer to do all this, I left it that way.
The seatbelts were not connected to the buzzer before anyway, so no change there. The glove box lamp still works and I can find nothing else not functioning as a result of leaving the module unplugged.
So can anyone think of a reason to plug it back up?
And, no, I can't account for the failure of the W/O to energize in the first place. Any ideas about that?
 
Re: 74 TR6 "seatbelt module"

No harm in leaving disconnected, IMO. You've already installed the required jumper between WO & WR, just make sure it's secure.

The purple wire is only power to the module, the module has nothing to do with the glove box light beyond getting power from the same place.
 
Re: 74 TR6 "seatbelt module"

/bcforum/images/%%GRAEMLIN_URL%%/banana.gif /bcforum/images/%%GRAEMLIN_URL%%/banana.gif I'm feeling better! /bcforum/images/%%GRAEMLIN_URL%%/thankyousign.gif
 
Re: 74 TR6 "seatbelt module"

I'll take your buzzer if you are thru with it. Need it for my fuel pump warning.
 
Re: 74 TR6 "seatbelt module"

PB,

I had starting problems with my '74 until I jumpered the same terminals on the SBM plug. I removed the entire module and its been starting great for 4 years. I also had to clean the pins in the starter switch plug. They got corroded and starter engagement got intermittent.

Jeff

TR6 CF13816U
 
Re: 74 TR6 "seatbelt module"

DNK said:
I'll take your buzzer if you are thru with it.
Click to expand...
You might want to rethink that, Don.
1) It's a logic module, not just a simple buzzer
2) Most likely it died (explaining why Ol Basil suddenly wouldn't start until the module was jumpered.
 
Re: 74 TR6 "seatbelt module"

Don, I imagine Randall is right. I can't think of any other explaination, but if you want to try it,letme know.
TRopic6, that's encouraging! Thanks.
 
Re: 74 TR6 "seatbelt module"

I removed seat sensor and module as well,but I wired jumper wire thru a toggle switch(hidden under the pass.side of dash) and use it as an anti theft device.The ignition switch can be jumped but starter won't turn.
 
Re: 74 TR6 "seatbelt module"

poolboy said:
Don, I imagine Randall is right. I can't think of any other explaination, but if you want to try it,letme know.
TRopic6, that's encouraging! Thanks.
Click to expand...

Can you give it 12 volts 2 test?
 
Re: 74 TR6 "seatbelt module"

Don, I can do that. I'm guessing that you just want to see if I can get the warning buzzer to sound?
There are 12 terminals on the module. I see that #4 is for the positive from the fuse box and #9 is ground. 11, 12 and 1 are for starting the engine.
That leaves 7 possibilities. Should I just make the ground connection at 9 then touch each one of the other 7 with 12v positive and see which, if any. sound the buzzer?
 
Re: 74 TR6 "seatbelt module"

I thought the buzzer was this?
Is this not what you have?
Buzzers.png
 
Re: 74 TR6 "seatbelt module"

No, that's not it. Take a look at Moss part # 542-360. That's what we are dealing with. In the Moss illustration you will see a rectangular metal housing. The part that protrudes is the built-in buzzer and the upper circle in the illustration represents the 12 pole socket.
 
Re: 74 TR6 "seatbelt module"

Not absolutely certain, but I think the buzzer gets it's power from terminals #1 (+12v) & #9 (ground). Then you can play around with grounding terminals #2 &/or #3 or #5 &/or #6 to see if you can get the buzzer to work.

Unfortunately I don't have Dan's book handy, and his schematic isn't clear about whether those switches are normally open or normally closed. But the logic should be that the buzzer only sounds when the key is on (power on #1), and a seat switch indicates someone is sitting in the seat, and the corresponding belt switch indicates they are not wearing their belt.

If the car started before with all 4 switches disconnected, then I'd guess that grounding either #2 or #5 would cause the buzzer to sound.
 
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