Triumphrat

CYNCRZR · 01-11-2006, 11:23 PM

Noticed the tailight was out. Checked the bulb and both filaments were intact. Popped the bulb in my Sportster & it worked fine. Tailight & Brakelight.

Grabbed the multi-meter and check for power at the wiring harness. 18v to both wires. Checked power at the poles in the tailight socket. 18v to both!.. when I put the ground lead on the tailight socket only 10v..hmmm

I'm mystified ? put the bulb from the Sportster in the Thrux. No Joy!

Checked to be sure the poles on the bulb are making contact with the poles on the socket. Looks like they are.

Had to go out for a bit, and driving home I'm thinkin, it's gotta be some kind of ground issue. Two wire tailight so I'm not really sure how it grounds.

Strip the ends of a short piece of wire, and with the key on touch the side of the tailight bulb socket and a bolt on the frame & Viola the light comes on! take it off, the light goes off. Do it again same result. Touch it a third time (I think, I really lost count of how many times I did it), this time the light stays on.

Turn the key on and off a couple of times and it seems to work fine now.

The question is Why ?

dazco · 01-11-2006, 11:55 PM

This is so typical of the kind of seemingly senseless things you find from time to time with electrics. My first guess would be dirty contacts. Second would be a loose connection of the contacts INSIDE the bulb, tho i got a bit confused reading your post and all the things you tried so those may have already been ruled out.

What i'd do is to put the bulb in and light her up, then with the seat off tug and pull at all the relevant wires and see if it flickers or goes off. If so, try and localize the problem.

Ok, just looked at the wiring diagram for thrux. Couple things struck me......check the fuse for dirty contacts or looseness. With the light on tap the fuse and surrounding area. Also look at the connector the tail light goes to.

vinnyf · 01-12-2006, 12:11 AM

Cheers, CYNCRZR,
I would second dazco's diagnosis - you have a bad connection between the light and the power source. The reason your meter says there's plenty of voltage is because the meter doesn't put a load on the circuit, while the light does. If you were to meter the circuit with the lightbulb in place, your results would be more meaningful (but more difficult to make, of course!) I'd check any connections in the circuit for corrosion, make sure all connectors are properly crimped, and the lamp socket itself is shiny metal. You can get a little fiberglass brush at your local Radio Shack to clean the contacts, and a can of contact cleaner to clean up contacts and connectors. If you're really into it, most electronic supplies carry a product called DeOxit or DeOxit Gold.

Good Riding!
vinny

CYNCRZR · 01-12-2006, 10:32 AM

Gentlemen, thanks for the responses. I'm still convinced it's a problem with the ground. Since after verifying I had power the cure was to temporarily ground the socket to the frame with a piece of wire.

What's really got me stumped is, why does it work now since the temporary ground is removed ??

Is it that the bulb isn't grounding well to the socket, or the bracket isn't grounding well to the frame ?

Anyway, stay tuned, I'll let ya know if I come up with anything more on the subject.

I guess this is fitting since it's a "Lucas" style tailight!

vanpraag · 01-12-2006, 03:33 PM

I think you may have stated your solution...

"Is it that the bulb isn't grounding well to the socket, or the bracket isn't grounding well to the frame ?"

:-D :-D

Slinky · 01-13-2006, 03:50 AM

Quote:

On 2006-01-12 08:32, CYNCRZR wrote:

I guess this is fitting since it's a "Lucas" style tailight!

I have learned the hard way that those aftermarket lights are pretty *****, quality wise. They are made somewhere like Taiwan or China and they are not up to the quality of the OEM stuff.

I had that "lucas style" light on a chop once, & had to replace it a few times.

dazco · 01-13-2006, 10:48 AM

Quote:

They are made somewhere like Taiwan or China and they are not up to the quality of the OEM stuff.

the OEM stuff is made in asia too ! Not sure where, but triumph outsources the lighting from asia as does harley. The Chris products turn signals i bought are better quality than the stock units, so don't assume aftermarket lighting is not as good as OEM. In fact, theres a lot of it thats very high end billit stuff with top notch sockets dn relectors and all. I'd say aftermarket is as good in the worse case scenario and better more often than not.

Slinky · 01-13-2006, 12:42 PM

[quote]
On 2006-01-13 08:48, dazco wrote:

Quote:

. I'd say aftermarket is as good in the worse case scenario and better more often than not.

You obviously haven't seen some of the aftermarket stuff I've seen then. There is some real garbage around.

rodburner · 01-13-2006, 10:07 PM

Cyn, I agree, grounding problem.Touching a wire from the light to the frame can cause a small arc to a place on the frame that is metal to metal. It will probably corrode or oxidize in a day or two and the light will go out again.Unlike cars,my Bonnie has isolated fenders that required a seperate ground wire for every light. A paint free ground point for the lights and the frame to battery cable should keep you going.

CYNCRZR · 01-17-2006, 11:48 AM

Mystery Solved! It was a problem with grounding the TailLight, not the bulb. Went out for a ride yesterday, stopped after a few miles and it was still working, when I got home it wasn't. This time I did my test from the TailLight itself to the the ground wire that comes outta the wiring loom and Viola light.

So I made up a ground wire the runs from the bolt that attaches the TailLight to the Bracket & from there to the GroundWire in the wiring loom.