Author Topic: help identify disconnected wires 67  (Read 1500 times)

Offline 67gta289

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help identify disconnected wires 67
« on: May 03, 2018, 07:38:10 PM »
To round out the electrical related posts today, I have two unused connectors, and am looking for help to determine what they are.  I combed, better stated scrubbed, the schematics but did not find any clues.

Referencing the attached picture, both of these wires are in the ignition switch/ash tray area.

One is light blue/red and the other connector has a double purple wire.

Thanks in advance
John
67 289 GTA Dec 20 1966 San Jose
7R02C156xxx
MCA 74660

Offline 67gtasanjose

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Re: help identify disconnected wires 67
« Reply #1 on: May 03, 2018, 08:16:19 PM »
One black spade connector plugs into the ignition switch and the other is a lamp feed, un-used excepting optional/dealer installed things.
Richard Urch

1967 (11/2/66, S.J.) GTA Luxury Coupe, 289-4V w/Thermactor Emissions, C-4, Int./Ext. Decor +many options

2005 (04/05) GT Premium Convertible, Windveil Blue, Parchment Top w/Med. Parchment interior,  Roush Body Appointments

Offline midlife

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Re: help identify disconnected wires 67
« Reply #2 on: May 03, 2018, 09:07:59 PM »
One black spade connector plugs into the ignition switch and the other is a lamp feed, un-used excepting optional/dealer installed things.
You took the words right out of my keyboard.  +1.
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Offline 67gta289

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Re: help identify disconnected wires 67
« Reply #3 on: May 04, 2018, 09:20:51 PM »
OK that makes sense, thanks.  But I'm still inquisitive as to the two purple wires attached to the single black connector.  These wires are part of the main harness, not the optional convenience control, A/C, etc.

I scoured the 11x17 1967 Ford electrical diagrams and could not find this connection anywhere.

If nobody knows I have a few extra harnesses, and will at least track down where the purple wires go, that should do it.

John
67 289 GTA Dec 20 1966 San Jose
7R02C156xxx
MCA 74660

Offline midlife

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Re: help identify disconnected wires 67
« Reply #4 on: May 04, 2018, 09:32:45 PM »
The purple wires go to a stud on the side of the ignition switch.  One of the wires ends up on the red molded connector that goes to the master cylinder; the other wire goes to the gauge.

I can't figure out why they routed it to the ignition switch, unless it was intended to be part of the proof-out circuit.  With the 67 ignition switch, there is no proof-out circuit built in.  I suspect it was a remnant design feature that Ford abandoned at the last minute in the ignition switch.
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Offline 67gtasanjose

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Re: help identify disconnected wires 67
« Reply #5 on: May 05, 2018, 11:36:32 AM »
The purple wires go to a stud on the side of the ignition switch.  One of the wires ends up on the red molded connector that goes to the master cylinder; the other wire goes to the gauge.

I can't figure out why they routed it to the ignition switch, unless it was intended to be part of the proof-out circuit.  With the 67 ignition switch, there is no proof-out circuit built in.  I suspect it was a remnant design feature that Ford abandoned at the last minute in the ignition switch.

I am not sure I would describe the wiring the way you have (underlined). "Master cylinder", I would have used "'Brake Light switch' (on Distribution Block)" and "gauge" I would have written '"Brake" warning lamp (in cluster)"

Otherwise, I have confirmed on a dissected harness that the black purple wire goes to both, from the pair of wires at the spade connector, connected to the ignition switch.

I might add that the circuit provides a "ground path" for the brake warning lamp in the instrument cluster, to help describe "function".
FWIW, at the 4-wire red molded connector (under dash, at firewall, engine harness to underdash harness connectors), the black/purple wire changes color in the engine harness to lavender/white.
« Last Edit: May 05, 2018, 09:07:42 PM by 67gtasanjose »
Richard Urch

1967 (11/2/66, S.J.) GTA Luxury Coupe, 289-4V w/Thermactor Emissions, C-4, Int./Ext. Decor +many options

2005 (04/05) GT Premium Convertible, Windveil Blue, Parchment Top w/Med. Parchment interior,  Roush Body Appointments

Offline midlife

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Re: help identify disconnected wires 67
« Reply #6 on: May 05, 2018, 06:58:18 PM »
I use short-hand destinations when I'm in a hurry.  The distribution block is more correct than the master cylinder.  And I should have said the gauge or dash cluster. 

On a 67, the red molded connector is 4 pins; for a 68, it is a 5 pin plug. 
Have you confirmed that the violet wires do not interact electrically with the ignition switch?
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Offline 67gtasanjose

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Re: help identify disconnected wires 67
« Reply #7 on: May 05, 2018, 09:06:31 PM »
I use short-hand destinations when I'm in a hurry.  The distribution block is more correct than the master cylinder.  And I should have said the gauge or dash cluster. 

On a 67, the red molded connector is 4 pins; for a 68, it is a 5 pin plug. 
Have you confirmed that the violet wires do not interact electrically with the ignition switch?

After reading the wires again referred to as "purple", I have edited my previous answer from black/purple to just "purple". I thought in the poor lighting, it was black w/purple tracer but since then, taken the harness to better lighting. Purple it is!

No, I have not checked the ignition switch for function to see if it provides a 'bulb-test' to the brake warning light. I find it interesting that if indeed a test proves no function to this circuit. Perhaps another reason for the switch change-out in the 68 model year? I know the design is poor quality for 67's and when there are many options, it is common for the switch and/or connector to melt-down. I sure like the idea of relay centers used on modern cars for this reason!
« Last Edit: May 05, 2018, 09:08:40 PM by 67gtasanjose »
Richard Urch

1967 (11/2/66, S.J.) GTA Luxury Coupe, 289-4V w/Thermactor Emissions, C-4, Int./Ext. Decor +many options

2005 (04/05) GT Premium Convertible, Windveil Blue, Parchment Top w/Med. Parchment interior,  Roush Body Appointments

Offline 67gta289

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Re: help identify disconnected wires 67
« Reply #8 on: May 06, 2018, 07:10:00 PM »
Thanks again for the replies.  I confirmed that the ignition switch terminal being discussed is isolated from all other terminals in every switch position including cranking.

It does appear that someone's idea did not make it through to the end.   
John
67 289 GTA Dec 20 1966 San Jose
7R02C156xxx
MCA 74660

Offline 67gtasanjose

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Re: help identify disconnected wires 67
« Reply #9 on: May 06, 2018, 07:58:12 PM »
Thanks again for the replies.  I confirmed that the ignition switch terminal being discussed is isolated from all other terminals in every switch position including cranking.

It does appear that someone's idea did not make it through to the end.

Did you try checking the pin for continuity to the case (ground) of the ignition switch (in "start")?
Richard Urch

1967 (11/2/66, S.J.) GTA Luxury Coupe, 289-4V w/Thermactor Emissions, C-4, Int./Ext. Decor +many options

2005 (04/05) GT Premium Convertible, Windveil Blue, Parchment Top w/Med. Parchment interior,  Roush Body Appointments