backup lights

[Ronnie K]

I have a 56 thunderbird with problems with the backup lights. I understand the wiring for the backup lights runs under the carpet, two red and black go out to the neutral safety and two black back inside. My back up lights are not wired in, do they go to the black wires? I also understand that the lights may have to be on. I have no currant at the black and red going to the switch or the black ones where they come back inside, even with the ignition switch on and the lights on. Are these two black wires hot? After a little more looking I see the two wires going to the safety switch look like they are already wired to the ignition switch, one on the middle terminal, the other on top but no power. Also, are the back up lights wired separately to the two black wires coming from the switch?

[Joe Johnston]

Ronnie K - Welcome to the VTCI Forum. Many experienced owners here. Tracing electrical issues can be tough to do over the internet. The Electrical manual & the Trim and Sealer Manual used together will show the circuitry and the routing of all the wiring.

You said:

My back up lights are not wired in,

Do you mean you have no wires at all connected to your back up lights? If so, would it be possible a previous owner added them just for looks and never made them functional?

Yes as wired originally the headlights, but not the ignition switch, must be on and it is a small safety improvement to relocate the back up light power supply wire from the headlight switch to the acc terminal of the ignition switch. Also (If your car has an automatic transmission) the backup/neutral safety switch can be modified or a new style purchased to allow starting in Park .

Keep us posted.
J

[paul2748]

It's been awhile since I did my 56, but if I remember correctly there is one wire that goes to the neutral safety switch (automatic) from the light switch and one wire out to the backup lights with a connector at the rear to go to both lights. The electrical diagram shows a black wire with a red tracer for the whole system. The wire going to the front is connected to a different section of the harness. If you have no wires there now, just run a separate wire right to the accessory terminal of the ignition switch for power.

I am unfamiliar with the standard shift version, but I believe that the switch is on the shifter underneath the floorboard, comes up through a hole and then to the rear. Again, the wiring diagram shows all wires are black with a red tracer. The rest of the standard shift harness is run like the auto version per the wiring diagram.

For a more detailed schematic, get the 1956 Thunderbird Electrical Assembly Manual which shows the routing, wire color and diagrams. Definitely worth the price if your working on your TBird.

[Ronnie K]

From Ronnie K I'm sorry but I am totally confused about these backup lights. Let me start over completely. My 56(automatic) had no backup lights at all, I understand that in 1956 they weren't required. I installed new sockets. Then I find the harness under the carpet has two wires, black and red, going out to the neutral safety switch, and from there two wires coming back into the car,black. These two wires are not connected to anything. I used my tester light and found no power any where, at the switch or at the wire coming inside, lights on Ignition on. I followed the wires up under the dash and unhooked them and plugged in a known power source. Now I have power, no backup lights and the car won't start. I hooked everything back up original and it starts. I might look for another switch altogether. If someone knows of this particular situation, I'll be glad to hear. Thank you Ronnie K

[55Greg&Amy]

If you have never had back-up lights then start here. Use your continuity tester and hook one lead to each of the unused plugs on the neutral safety switch. When you shift to reverse you should have continuity. If so, then those are the ones for the backup circuit and the switch is working properly.

There are 4 wires on the neutral safety switch: 2 of them are Red with a Black tracer that are for the neutral start. The other 2 are Black with a Red tracer and those are for the back-up lights and should currently not have anything plugged into them.

Plug your wire from the backup lights into 1 of those connections. The other connection should be connected to a Black wire with a Red tracer that exits from under the carpet and above the firewall insulation. There are a few wires in this harness (4 or 5) and it should be a cloth covered harness. Find the black wire with a red tracer and from there you have 2 options.

Option 1: originally that wire was connected into a 4 way junction that has a solid black wire which gets its power from the R terminal at the headlight switch. This option requires you to have the headlights on for the back-up lights to work.

Option 2: Disconnect that Black wire with Red tracer from the junction and connect that Black wire with Red tracer to the A terminal of the ignition switch (the one with the most wires connected). This option will make the back-up lights operate just like your daily driver, back-up lights will come on whenever you have the car started or in the accessory position and put the gear selector into reverse.

[Ronnie K]

Thank you Greg, I now have backup lights Ronnie

[swatson999]

...
There are 4 wires on the neutral safety switch: 2 of them are Red with a Black tracer that are for the neutral start. The other 2 are Black with a Red tracer and those are for the back-up lights and should currently not have anything plugged into them.

...
Find the black wire with a red tracer and from there you have 2 options.

Option 1: originally that wire was connected into a 4 way junction that has a solid black wire which gets its power from the R terminal at the headlight switch. ...

Option 2: Disconnect that Black wire with Red tracer from the junction and connect that Black wire with Red tracer to the A terminal of the ignition switch (the one with the most wires connected). This option will make the back-up lights operate just like your daily driver, back-up lights will come on whenever you have the car started or in the accessory position and put the gear selector into reverse.

Quick question...I'm not at home at the moment, but I'd like to look at doing this when I get there. Where is this junction located? It's not that standard Ford sort of block with the bullet plugs on the wires that is tucked up under the driver's side dash, is it? (I'd check my wiring diagrams, but those are at home, too, and none of the available ones on-line show the backup light circuit).

Thanks!

[paul2748]

The back up light switch is located on the transmission or the shifter if a stick car and is part of the neutral safety switch if an automatic car. In stock form, the power wire comes from the light switch to the backup light switch and from there to the back up lights. See my earlier explaination above

You should get an Electrical Assembly manual. It has routing and color codes.

Quick question...I'm not at home at the moment, but I'd like to look at doing this when I get there. Where is this junction located? It's not that standard Ford sort of block with the bullet plugs on the wires that is tucked up under the driver's side dash, is it? (I'd check my wiring diagrams, but those are at home, too, and none of the available ones on-line show the backup light circuit).

Thanks!
[/quote]

[MarkR]

This conversation appears to be from the past. 8 years ago. ??? I think Ronnie K is long gone.

[ward 57]

But doesn't it bounce off Rossl's post about adding back-lights? An investigation of old posts does come to fruition.

[MarkR]

I see that. Thanks for pointing it out.

[Jimntempe]

...
There are 4 wires on the neutral safety switch: 2 of them are Red with a Black tracer that are for the neutral start. The other 2 are Black with a Red tracer and those are for the back-up lights and should currently not have anything plugged into them.

...
Find the black wire with a red tracer and from there you have 2 options.

Option 1: originally that wire was connected into a 4 way junction that has a solid black wire which gets its power from the R terminal at the headlight switch. ...

Option 2: Disconnect that Black wire with Red tracer from the junction and connect that Black wire with Red tracer to the A terminal of the ignition switch (the one with the most wires connected). This option will make the back-up lights operate just like your daily driver, back-up lights will come on whenever you have the car started or in the accessory position and put the gear selector into reverse.

Quick question...I'm not at home at the moment, but I'd like to look at doing this when I get there. Where is this junction located? It's not that standard Ford sort of block with the bullet plugs on the wires that is tucked up under the driver's side dash, is it? (I'd check my wiring diagrams, but those are at home, too, and none of the available ones on-line show the backup light circuit).

Thanks!

My car didn't have backup lights so I added them. As to wiring, what I found was that under the carpet by the transmission shifter area there were the wires from the Neutral safety switch/backup light switch. They were just the pigtails, not connected to anything because my car didn't have the BU lights. I ran switched power from the dash down the doorsill, then sideways to the location of the pigtails and used the factory BU switch and ran the "out" wire back to the doorsill area and on back into the trunk and connected it to the backup lights. After I did that I found what looked like OEM unused BU light wires down under the tail lights so it may be most of the wires are already there, you'd just need to run one switched power wire TO the switch and find the end of the trunk wires, not sure where they come out since when I discovered they existed it was too late to use them. This photo shows what I found but I'd already taped down a lot of the wires so it's not a clear as it might otherwise be.

[swatson999]

The back up light switch is located on the transmission or the shifter if a stick car and is part of the neutral safety switch if an automatic car. In stock form, the power wire comes from the light switch to the backup light switch and from there to the back up lights. See my earlier explaination above

You should get an Electrical Assembly manual. It has routing and color codes.

Quick question...I'm not at home at the moment, but I'd like to look at doing this when I get there. Where is this junction located? It's not that standard Ford sort of block with the bullet plugs on the wires that is tucked up under the driver's side dash, is it? (I'd check my wiring diagrams, but those are at home, too, and none of the available ones on-line show the backup light circuit).

Thanks!

[/quote]

This was exactly no help whatsoever. I KNOW where the SWITCH is located, that's not what I'm asking. I DO have the electrical assembly manual AT HOME, which is not where I am. I was just asking about the JUNCTION which connects the single black wire from the headlight switch R connector to multiple lamp circuits, including the backup lights...so that I can see about moving that to the ACC terminal on the ignition switch. As in...where's this junction and how easy is it to get to?

It's not important, I obviously can sort it out later, I was just curious and planning ahead a bit.

originally [the backup light from the switch on the tranny] wire was connected into a 4 way junction that has a solid black wire which gets its power from the R terminal at the headlight switch. ...

Option 2: Disconnect that Black wire with Red tracer from the junction and connect that Black wire with Red tracer to the A terminal of the ignition switch

[paul2748]

I'm answering a new question from another posting right above mine.

This conversation appears to be from the past. 8 years ago. ??? I think Ronnie K is long gone.

[paul2748]

#1 you don't have to get snippy when somebody tries to help you. # 2, all you have to do is trace the wire from the switch forward to find out where the wire is tied in - but you already knew that, didn't you ??

This was exactly no help whatsoever. I KNOW where the SWITCH is located, that's not what I'm asking. I DO have the electrical assembly manual AT HOME, which is not where I am. I was just asking about the JUNCTION which connects the single black wire from the headlight switch R connector to multiple lamp circuits, including the backup lights...so that I can see about moving that to the ACC terminal on the ignition switch. As in...where's this junction and how easy is it to get to?

It's not important, I obviously can sort it out later, I was just curious and planning ahead a bit.

originally [the backup light from the switch on the tranny] wire was connected into a 4 way junction that has a solid black wire which gets its power from the R terminal at the headlight switch. ...

Option 2: Disconnect that Black wire with Red tracer from the junction and connect that Black wire with Red tracer to the A terminal of the ignition switch