Tailight wiring 72 XY Ranchero

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Ou Toppie
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Joined: Wed 08 Oct 2008, 12:29

Tailight wiring 72 XY Ranchero

Post by Ou Toppie » Mon 22 Aug 2011, 15:52

Hi Guys,

Took the 72 XY Ranchero out for a spin around the block after more than two years of restoration. Lots of power, just a few small items to rectify.

One of these is the wiring to the taillights. With a new switch from Auz and all the wiring kept in the same colour codes, the problem is the following.

By puling the swith out to the first notch, the parklights will lit

By puling the switch out to the second notch , the headlights will come on, but the taillights will switch off.

The three main connections on the switch are B = Battery, P=Park and H=Head

Measured with a multimeter over B and P when the switch is puled out on first notch, shows continuity. Over B and H with switch puled to second notch shows continuity, however measuring between B and P then is disrupted.

Taillight lamp has two filaments. Park and stop. Only way I see is to bridge P and H and have Parks working with headlights.

See wiring diagram below.

Cheers

Ou Toppie
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XYFalconFairmontZDFairlaneFuturawiring%20in%20colour.gif (150.35 KiB) Viewed 1825 times

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Ou Toppie
Posts: 124
Joined: Wed 08 Oct 2008, 12:29

Re: Tailight wiring 72 XY Ranchero

Post by Ou Toppie » Tue 23 Aug 2011, 12:06

Hi Guys,

Seems I have stun you with this one.

Where are all the experts?

Cheers

Ou Toppie

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paulusvrotius1
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Location: Southampton UK

Re: Tailight wiring 72 XY Ranchero

Post by paulusvrotius1 » Tue 23 Aug 2011, 12:24

Hi Ou Toppie,

According to your wiring diagram you need to have both H and P terinals live in order for your lights to work as you have already tested.

I would say that if P is losing connection when you switch to H the switch itself must be faulty as this would not work on any car.
Also check the 14A fuse that supplies the cigar lighter as this may supply a feed for the tail light circuit when the knob is in the second position.

You could wire both circuits to the H terminal but you would lose the park function.
If you wired H and P together you would have all lights on at the same time when selecting first and second notch on the knob.

Are your other light functions working eg dash, interior etc.

Does the switch have all the other terminals also and looks the same?

Hope this helps.

Cheers

Paul
Last edited by paulusvrotius1 on Tue 23 Aug 2011, 12:38, edited 2 times in total.
Cheers

My AMC:
1971 Capri Perana Yellow/Blk.


Old Fords never die because some clotheads keep bodging them back together!!

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wareling
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Location: Johannesburg

Re: Tailight wiring 72 XY Ranchero

Post by wareling » Tue 23 Aug 2011, 12:31

Hi There

I used exactly the same wiring diagram to get my '69 XT sorted out. Tell me, when the taillights go out, what happens to the front park lights (should also be a twin filament with the front indicators)?

Cheers
Francois
Overspecialize, and you breed in weakness

I Have:
'69 Fairmont XT (351C / C4 / 9" 2L75)
'57 Chrysler Imperial Crown (????)
'60 F100 (256 Y-Block)

'71 Fairlane 500 (351C/..../9" 2L75)

I Want:
'67 Pontiac GTO

My Wife wants:
ME!

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Neek
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Joined: Sat 13 Aug 2011, 09:20
Location: Cape Town

Re: Tailight wiring 72 XY Ranchero

Post by Neek » Tue 23 Aug 2011, 12:50

Hi Ou Toppie,

I'm colour blind. Do you happen to have a black and white diagram ? :lol: :lol:

On a serious note, Wareling is asking the question I wanted to !!

The B and BY wires in the diagram are part of one circuit, front (park) and rear lights.
So if the rear go off and the front stay on, there's an implied solution to the problem.
If you're lucky enough to have a V8, you're lucky enough !

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Neek
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Joined: Sat 13 Aug 2011, 09:20
Location: Cape Town

Re: Tailight wiring 72 XY Ranchero

Post by Neek » Tue 23 Aug 2011, 12:59

My eyes are starting to blurr.

Swap the P and H wires around.
If the same pattern occurs with lights going off and multimeter readings, I'm going to go with a faulty switch.
If you're lucky enough to have a V8, you're lucky enough !

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Ou Toppie
Posts: 124
Joined: Wed 08 Oct 2008, 12:29

Re: Tailight wiring 72 XY Ranchero

Post by Ou Toppie » Tue 23 Aug 2011, 14:15

Hi Guys,

Let me tell you I have also suspected the switch and have therefore imported a new one, just to find it has the same configurations.

Front park and indicator lamps have separate single filaments. Stop/tail lamps are dual filament.

All other lamps are working fine. I will keep the connection over P and H and have all lights working on both notches........unless someone comes up with another suggestion.

Cheers

Danie

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Neek
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Joined: Sat 13 Aug 2011, 09:20
Location: Cape Town

Re: Tailight wiring 72 XY Ranchero

Post by Neek » Tue 23 Aug 2011, 14:20

Hi Danie.

When you pull the switch to P, the rear lights come on, and so do the front park lights.

But, when you pull the switch to H, do the front park lights stay on, or do they also go off ?
If you're lucky enough to have a V8, you're lucky enough !

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Ou Toppie
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Re: Tailight wiring 72 XY Ranchero

Post by Ou Toppie » Tue 23 Aug 2011, 14:47

Hi Neek,

Second notch H, both park and tail lights go off...only headlights working.
First notch P, both park and tail including numberplate lamps on.....headlamps off.

Another fault in the wiring diagram I found is the wiring to the headlamps after the dipswitch. The High Beam indicator lamp should be connected to the RB wire which feeds the High Beam.

Cheers

Danie

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paulusvrotius1
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Joined: Fri 22 Apr 2011, 15:40
Location: Southampton UK

Re: Tailight wiring 72 XY Ranchero

Post by paulusvrotius1 » Tue 23 Aug 2011, 15:12

Hi Danie,

Are you getting a live on the Green/Yellow terminal on the switch, and have you checked the cigar lighter has a positive on it?
This is the only other positive feed going to the switch.
Also check for continuity between the Gn/Y terminal and P with the switch pulled in both positions.

Yes I noticed the highbeam lamp on the wrong wire, forgot to mention it. :oops:

The other thing is, this diagram is for 1970 models so may be wrong for your car, hence the double and single fillament front lamps, and we are looking in the wrong place for a solution.

Cheers
Last edited by paulusvrotius1 on Tue 23 Aug 2011, 15:41, edited 3 times in total.
Cheers

My AMC:
1971 Capri Perana Yellow/Blk.


Old Fords never die because some clotheads keep bodging them back together!!

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