View Full Version : TR2/3/3A Horn and Signal harness TR3

11-23-2008, 05:07 PM
I purchased a TR3 a couple of months ago and this is my first post. The TR3 has been in storage for several years and I am working though some bugs. It has a 1.7 amp power drain and the PO thought it may be the horn /signal harness or control head. Can someone tell me where the harness exits the steering column to tie into the main harness? The horn and signals had been hooked up to a buttons on the dash but the PO thinks the body shop reconnected the old wiring to the horn. I can't see where the wiring exits the shaft.


Steve Woodward
1961 TR3

11-23-2008, 05:37 PM
the wiring harnes exits out the bottom of the steering box look under the front apron and you should see a wire come out of the steering tube.

11-23-2008, 05:39 PM
It should exit out of the steering box proper. There is a tube that extends from the steering head down and thru the steering box where there is a nut and olive holding the stator tube stationary. The wires exit there and route upwards to the drivers side of the car where the headlamps/signal lamps tie into the harness by the grounds on the car body in the engine bay.

Russ Austin
11-23-2008, 07:12 PM
Welcome to the forum Steve as you can see there's help right around the corner, did you buy the yellow TR3 from Daniel in Evansville.

11-23-2008, 08:16 PM
I doubt that's where the problem is, though. The turn signal wires are not hot with the key off, and if the horn wire were shorted to ground, you would either get a lot of heat where the (partial) short is, or the horns would sound all the time.

11-23-2008, 09:26 PM
Hello Russ,
Thanks for the welcome aboard. No I missed Daniels by a couple of weeks and it went to a fellow from Jersy but I found one a little later on Craigslist over near Raligh NC. Trailer it back just as gas was at 4.00 a gallon :eeek: It is red like yours. I need to put the interoir back in, find the power drain and address a stubborn starting issue.

11-23-2008, 10:02 PM
The signals are funtioning on a dash toggle switch. I thought the same with the heat issue regarding a partial short however there is a drain somewhere. I unhooked one of two large brown wires(drivers side) hooked to the solnoid and that disconnected the drain. Both are large solid brown wires that appear original but my schematic shows only one brown wire going to the ammeter in the dash panel. Any thoughts on were the Lucas gremlin may be hiding?
The PO had no battery and said the system was a positive ground and I have it hooked that way, PG. The TR has been in storage for a while and if he was mistaken and it had been converted to a negative ground could this be the issue? Any way to verify which way the system is currently set to. Thanks for your assistance.

11-23-2008, 10:34 PM
For an excellent collection of TR wiring diagrams, check out: https://www.advanceautowire.com/

I've had them printed out at 11X16 size at my local Kinkos. They'll give you a head start on your car's electrics.

For an easy description of generator polarization, check out the back of the MOSS TR2-3-4-4A part catalog.... I believe it's also online, if you don't have one. There's also good info in the back on wiring color, and what different colors mean; brown wires are hot, and unfused.

Make sure your car has an engine ground strap!

Post some pix!

11-24-2008, 02:15 AM
Dunno what the second brown wire is, but the original one basically fed power to the entire car (except the starter). What happens if you pop out the horn fuse?

Switching the ground shouldn't cause a drain, unless some sort of electronics has been added. None of the original equipment cares all that much.

Two things to look at are the ammeter, and the coil. Of course if it was converted, they may or may not have been switched (the car will still run either way); but that's what I would follow.

Turn the headlights on (engine off) and check the ammeter, if it shows discharge (-) then the battery polarity matches the ammeter wiring.

At the coil, look for either +/- or CB/SW markings on the two side terminals. If the - or SW is connected to the distributor, the connections have been swapped for negative ground.

I know this is obvious, but have you looked at the car in the dark, to see if any lights are showing ?

11-24-2008, 11:25 PM
I checked the ammeter and it does show a negative reading with the ignition on, when the headlights create a load.

You were right about the horns I pulled the control head and found a 6 inch stub of wires and that explained why I couldn't find them coming out of the bottom of the steering gear box. I did locate the stator tube and olive nut. I also pulled the horn fuse and it had no effect on the drain.

When I remove the green/yellow wire on the bottom of the generator (brown on mine) it stops the drain. Mine is hooked to the second A lug on the control box/regulator instead of F lug like the schematic shows. Wondering if that could be the issue?

I need a new wiring harness. This one is pretty much a mess.

11-25-2008, 12:58 AM
When I remove the green/yellow wire on the bottom of the generator (brown on mine) it stops the drain. Mine is hooked to the second A lug on the control box/regulator instead of F lug like the schematic shows. Wondering if that could be the issue? Ayup! Both A and A1 are hot all the time, so having either one of the generator terminals connected directly to them would cause a constant discharge. Sounds like maybe your control box is sick, and the DPO found that moving the wires around would cause the generator to work some.

At least you know it doesn't need to be polarized <<GRAEMLIN_URL>>/grin.gif

PS, operating that way for very long can toast the generator. It needs the control box to limit it's output current, otherwise it will overheat.

11-26-2008, 11:15 PM
After closer inspection one of the yellow wires were also routed to the wrong terminal. I supect when the CB was removed at the body shop to paint the firewall and a couple of wires came loose then were put back without the aid of diagram. I am now showing zero drain.

Thanks for your help. :thumbsup:


Russ Austin
11-27-2008, 12:17 AM
Oh that's to weird Steve, great look car.