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Discussion Starter #1 (Edited)
Hi all,

Got a question for ya if you dont mind.

Full disclosure - I am going to sell these wiring harnesses so my info is to help me determine what I have for the sale - not to use on my 69 as I plan on going AAW.

Anyway, I have an underdash tach harness p/n C9Zb-14444-H and it has 14 pins on the main connector to the hood (13 small and 1 big) - pretty straight forward stuff.



BUT - I also have an under hood tach harness, cant find a p/n. But it has 16 pins (15 small and 1 big)!!





Can any of you guys tell me what the underhood harness is all about??? Why the 2 extra pins? I'm almost positive that both harnesses did NOT come off of the same car.

Thanks very much!
 

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The Ford tach was connected to the ignition switch feed wire to the coil. Then the tach connects to the pink resistor wire normally between the ignition switch and the firewall. The wire from the firewall to the coil is the ordinary feed wire. There is no GM-style wire from the distributor to the tach.

The principle difference in the tach-equipped cars was the change from AMP and OIL gauges to idiot lights.
 

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Discussion Starter #3 (Edited)
Hi GT, please excuse my ignorance on this subject. I am not as good on wiring as Id like to be. I still dont understand tho. I believe both these harnesses are for tach cars - right? But if so, what are the 2 extra pins on the hood harness(16 pin main connector vs 14)? Was it a car with more options? Sorry if I dont understand your answer above.

It looks like the pins wires are number 654 and 655 - but they are only on the under hood harness - and the dash harness block has no pins in those spots. But I am sure the dash harness it tach. Not sure about the under hood.
 

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The harness between tach and non-tach cars was different. But the tach was not why. The non-tach standard cars had full instrumentation, gas, temp, amp, oil, but the tach-equipped cars had no oil or amp gauge, just idiot lights, so the amp wiring was completely different, an only fed an amp idiot light. This required routing of the wires differntly on both the headlight and engine wiring, since the standard amp gauge was connected to the engine wiring, while the idiot light connected to the voltage regulator via the headlight harness.
 

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My original '69 wiring loom has the (16) pins (with (1) large).....it also has a trans switch for the 4 speed which comes off the pins.....looking at mine the green/red wire goes to the coil rather than a pink all the way...I understand this was only on the tach equipped '69...
22GT is correct with the alt/temp idiot lights...
Tom
 

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My original '69 wiring loom has the (16) pins (with (1) large).....it also has a trans switch for the 4 speed which comes off the pins....
For standardization, in 67 Ford started using the same wiring harness connector for manual and automatic. The neutral safety switch, or backup switch had the same plug on the end of the wire, but the backup simply had a loop to connect the NS wires together so the starter would work. Pretty slick, really. For one thing, it makes converting any 67-73 Mustang to a T5 manual a snap, electrically.
 

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Discussion Starter #8
Well this all seems to make sense - I think......lol.

I know the dash harness is a tach harness - as it has the C9ZB14001-AJ NA-14444-H number on the purple tag. Those match the tach harness part numbers. I believe you are telling me that just because its a tach harness that it doesn't increase the pin count. It has 14 pins

But my under hood harness has 2 more connectors than the under dash - it has 16. So I think what I have here is a non tach under hood harness. And the 2 extra pins are for the guages. Kinda makes sense!

Thanks so much for all your help! I do plan on learning much more about wiring in the near future!!! I better learn - since I am going to rewire my car.....lol.

Thanks again!
 

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You can get new harness, or even have the old one reconditioned.
 

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But my under hood harness has 2 more connectors than the under dash - it has 16. So I think what I have here is a non tach under hood harness. And the 2 extra pins are for the guages. Kinda makes sense!
This is correct. I just received a new under hood wire harness for a 69 w/out tach and it has 16 pins. The instructions say terminals 11 & 12 (the 2 stacked ones next to the screw hole) are not used for a 69 w/tach so that would indicate only 14 pins for a tach harness.
 
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