TR2/3/3A Flasher Unit, A Clue?

Hi Guys,

Just to give some quick history, my 59 TR3 has been wired a thousand times...at least it looks that way. It's nearly impossible to follow, say, a green wire in the wiring sheath and expect to find a green wire coming out of the harness sheath. So that makes it kind of tough to trace problems.

I know there have been a ton of posts on turn signal problems, and I have one. I've managed to get my left turn signal working, but I'm having no luck getting the right signal working. According to the wiring diagram a green and white wire supplies the right signal. I can't find power to the green and white wire wherever I test it. That should be a clue, right? But my tiny mind can't figure it out.

OK. Here's a weird one, but I think an important clue for someone who has a brain (certainly not me). When I was troubleshooting my left signal, I replaced the flasher unit. That wasn't the problem, but I just want to mention that it should be working fine, so we probably shouldn't focus on that, but here's the weird thing...

When the left signal is on and I touch the L terminal with my voltage tester, the tester light flashes. The X terminal is a solid light.

When I turn on the right signal, the signal doesn't work, but the L terminal on the flasher unit lights up the tester but does not flash...it just remains a solid light. And the X terminal is a solid light.

The other weird thing is the signal indicator on the dash used to work, but that's gone now too. I replaced the bulb, but nothing happens.

What am I missing? Anyone have any ideas?

Thanks! in advance.

Do yourself a mental health favor.....call British Wiring and get a new harness. They are not that hard to swap out and you're guaranteed to have 100% new, clean and correct wires, no breaks in the harness and no corrosion. This probably takes all the fun out of chasing gremlins but everything will work the first time.

RGW said:

Hi Guys,

Just to give some quick history, my 59 TR3 has been wired a thousand times...at least it looks that way. It's nearly impossible to follow, say, a green wire in the wiring sheath and expect to find a green wire coming out of the harness sheath. So that makes it kind of tough to trace problems.

I know there have been a ton of posts on turn signal problems, and I have one. I've managed to get my left turn signal working, but I'm having no luck getting the right signal working. According to the wiring diagram a green and white wire supplies the right signal. I can't find power to the green and white wire wherever I test it. That should be a clue, right? But my tiny mind can't figure it out.

OK. Here's a weird one, but I think an important clue for someone who has a brain (certainly not me). When I was troubleshooting my left signal, I replaced the flasher unit. That wasn't the problem, but I just want to mention that it should be working fine, so we probably shouldn't focus on that, but here's the weird thing...

When the left signal is on and I touch the L terminal with my voltage tester, the tester light flashes. The X terminal is a solid light.

When I turn on the right signal, the signal doesn't work, but the L terminal on the flasher unit lights up the tester but does not flash...it just remains a solid light. And the X terminal is a solid light.

The other weird thing is the signal indicator on the dash used to work, but that's gone now too. I replaced the bulb, but nothing happens.

What am I missing? Anyone have any ideas?

Thanks! in advance.

Click to expand...

The L (load) terminal not flashing indicates that the bulb isn’t in the circuit- it’s an open circuit. You’re using traditional lamps, not LED, right? Is the bulb good? I’d check all the grounds . Do you have a volt-ohmmeter, to check continuity in addition to your circuit tester ? I don’t do anything without my Simpson 260. The other thing that comes to mind is the state of your bullet connectors. British Wiring sells the crimping tool and all the bullets you need. Of course, they also sell new wiring harnesses...

I’ve had my own wiring demons, but they eventually work out — even tonight I had to rewire the R running light/turn signal light socket because I had them swapped.
Jim
TS 44743L “O”

Joe you beat me to it!

Thanks a ton, you guys. I'll take all your suggestions into the garage tomorrow, and I'll let you know what I find. In the meantime, if anything else comes to mind, please let me know!

Have a great evening.

Why did you change the flasher canister? I went through three or four new electronic flashers and had no joy until I went back to the original thermo points unit which now works as it should.

Graham

Graham,
Where did You order your thermo points unit from and do you have a part# or brand?
I've been through three so far, and ran good grounds from all bulbs, cleaned and checked traficator switch on my TR3B, and still no flash.
Thanks:
Jim

Hi Graham,

I just changed it because it had been on the car quite sometime, so I just did it. Wish I hadn't. And wish I hadn't tossed the old one.

But it does seem to be working. I'm thinking that since it is working for the left signal, it would work for the right signal as well...as long as I have the right signal wired correctly, which obviously I do not. But there is no question that I could be wrong.

Joe,

The funny thing is that I purchased a new harness last year, and it's hanging on the wall of my garage. And you are right, I should replace it, but I have to say I'm really intimidated to take that step. Right now, I have a car I can drive...I just can't signal a left-hand turn. I'm afraid that if I try replacing the harness, I'll end up with a car just sitting in the garage that I'm unable to drive.

But I have to say, I'm really tired of trying to make sense of all the previous owners' creative wiring. And I'm getting really tired of finding wires that go nowhere, and wires that have just been cut and are dangling.

So, can you give me some confidence to help me take that step?

When I bought my TR3A kit car (it was a failed restoration) it came with a British Wiring harness and everything went well as I installed in the car. I did add good grounds for all the tail lights. Also I did some mods to the harness as I went to an alternator.
The wiring behind the dash is fiddly but worth it if you have wiring gremlins.
The harness has a couple of spare wires that are in the flasher circuit to accommodate LHD and RHD cars. They can be confusing. Don't Ask how I know.

David

Might be the switch in the control head, they can be finicky, if the other side works you are getting power from the solid green wire to the TS circuit.

Jim,
I used the original out of the car,I only changed it because the outer casing was looking old and the mounting tag had broken off. I finished up using one of the new casings to fit the old unit into so it looks new. When I researched a replacement I think I found an MG or Morris Mini unit would work, you could check them out.

Graham