In a message dated 97-12-19 09:55:03 EST, DUHART@symbol.com writes:
> I am replacing my old wiring harness with one I bought through the net. It
is
> from a 75-76 TR6. It has the 12 pin circular modular connector for the '
> seatbelt warning system'. It also has the 'Starter relay'. It would seem
> that the WR (white Red) starter wire runs from the ignition switch to the
12-
> pin connector, and then from the connector to the starter relay.. Since I
> don't have the 'seatbelt warning system' device can I just connect the two
WR
> wires from the 12-pin modular connector.
Yes. Actually, the wire from the connector back to the relay should be
white/orange, but the colors fade with age.
> Also are there any other wires at
> the 12-pin modular connector that need to be connected. I checked
everything
> out and I didn't find any, but I wanted to check with the list.
No. However, there are two wires that may need to be insulated, depending on
how the connector is configured. The purple wire is hot all the time, and the
white wire is hot when the key is on.
> Also if anyone has an explanation on how the 'seatbelt warning system'
> device works I would appreciate an explanation.
There were sensors in each of the seats, and switches in the seat belt
buckles. When the seat sensers detected the presence of a butt, they opened an
internal switch. If the seat belt for that seat was fastened, the open switch
was bypassed by the seat belt switch. So, if you had a passenger, then the
passenger seat belt would need to be fastened. If not, then the belt didn't
need to be fastened.
As long as either the seat senser switch or the seat belt switch was closed,
power from the ignition switch was passed through the seat belt module to the
starter relay, and the car would start. If either switch was open, the relay
never received power, and the car wouldn't start.
In addition, there was a switch in the door jamb connected in series with a
switch in the ignition lock/key assembly. If the door was open and the key was
in the lock, both switches were closed and a buzzer sounded.
The actual details of the operation may differ from the above, but that's
basically how it worked.
Dan Masters,
Alcoa, TN
'71 TR6---------3000mile/year driver, fully restored
'71 TR6---------undergoing full restoration and Ford 5.0 V8 insertion - see:
http://www.sky.net/~boballen/mg/Masters/
'74 MGBGT---3000mile/year driver, original condition
'68 MGBGT---organ donor for the '74
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