What is the purpose of the brown wire on this steering rack?

[Whitephrog]

 

[BlueMax]

Thats funny!!:excitement:

 

[David_Doan]

Probably an attempt to make sure the steering column is grounded so the horn will work.

 

[Branson]

Grounded to itself? Electricity is a funny thing.

 

[Keith_M]

Probably an attempt to make sure the steering column is grounded so the horn will work.

I think this is right. I seem to remember a wire from the steering column to the frame. I think this is just misplaced.
Keith

 

[nomad]

Actually, there is a packing between the rack and the clamp that the ground wire attempt's to get around. Making the horn's work can be difficult. My 65 had a steel cable to ground that wrapped around the steering shaft when you turned. Appeared to be factory installed.

Kurt.

 

[Rut]

Actually, there is a packing between the rack and the clamp that the ground wire attempt's to get around. Making the horn's work can be difficult. My 65 had a steel cable to ground that wrapped around the steering shaft when you turned. Appeared to be factory installed.

Kurt.

With the steering rack electrically isolated by the packing between the rack tube and its mounts, this was their attempt to ground it for the horn. I painted my rack mount brackets and effectively insulated it and the horn didn't work.
Rut

 

[dklawson]

It may be a brown wire but for commonality with Lucas color codes it should be "black". As stated above, they are fitted to some non BMC cars (especially Triumphs) to make sure the horn circuit has a path to ground through the pinion on the steering column and the rack housing. On TRs there is typically a black wire from the front wiring harness that attaches to the rack with the other end connected to the chassis somewhere.

 

[Whitephrog]

This horn grounding thing my be the root of all my electrical issues with the Whitephrog. It wasn't unusual for the horn to operate for no reason at all. I seem to recall the horn sounding occasionally when the headlamps were turned on. I believe that all this may have fried the ignition switch.

 

[Guest]

I think ground on my 79 is brown

 

[nomad]

I believe that brown is supposed to be unfused hot. I'd have picked black, Doug.:chuncky: Unfused brown for the horn button circuit. Black after that.

Kurt.

 

[smaceng]

So I had the same problem that others had....horn would not work. Maybe I was wrong, but I insulated with fish paper the rack from the frame mounts as the factory specification. I can understand why the factory did this as the rack is steel and the mounts are aluminum. I do not think there is a good ground through the tie rods...may be they are rubber insulated? So I did what is suggested, I added the wire from the rack to the bolt which attaches the rack to the frame. What I want to know....how in the world did the factory get the horn to work reliably ????? As designed it is hit or miss.....as other have indicated.....as well as myself!
Any input would be appreciated. I think this is one of the only areas on my "old" 60FROG that I had to modify the factory design to make the car "operate."
Scott in CA

 

[PAUL161]

Not sure on Sprites, but Black is a Lucas standard for ground/earth. Brown is an, I think, unfused hot wire, with or without stripes. After all these years, who knows what's been changed on these cars. PJ

 

[Bayless]

That's right. Brown is unfused hot and ground is black. Of course who knows what some DPO may have added.

 

[Guest]

I'll have to check but I'd swear all of my lights are grounded brown on my 79 and it's an original unmolested harness.

 

[nomad]

So I had the same problem that others had....horn would not work. Maybe I was wrong, but I insulated with fish paper the rack from the frame mounts as the factory specification. I can understand why the factory did this as the rack is steel and the mounts are aluminum. I do not think there is a good ground through the tie rods...may be they are rubber insulated? So I did what is suggested, I added the wire from the rack to the bolt which attaches the rack to the frame. What I want to know....how in the world did the factory get the horn to work reliably ????? As designed it is hit or miss.....as other have indicated.....as well as myself!
Any input would be appreciated. I think this is one of the only areas on my "old" 60FROG that I had to modify the factory design to make the car "operateView attachment 36279."
Scott in CA

Scott, my 65 Midget had a small steel cable that attached at the steering shaft to rack pinion pinch bolt and went to the rack clamp frame attachment bolt. As you turned the wheel the cable would wrap around the steering shaft. Sure looked to be factory original.

Kurt.

 

[Sarastro]

I've always seen black for grounds on LBCs. However, for what it's worth, Bosch created a standard for wire colors, which is used in my '67 Porsche, and I suspect most or all other German cars. Maybe other European ones too. In that standard, brown is ground. So, it's not a great surprise that someone might be accustomed to that standard and just automatically used brown for a ground.

 

[dklawson]

For future reference, the link below is for Lucas wiring color codes. According to it, "In the United Kingdom the British Standard BS-AU7 determines colour coding of automobile wiring."

https://www.mgb-stuff.org.uk/colourcodes.htm

 

[histerical]

Wow . That chart is a treat. Thanks.

 

[jlaird]

After looking at the pic several times, I think it is a trick question. LOL