Triumphrat

Landshark

I have rewired my 1971 TR6R with new high quality cloth wrapped wire loom. I had the rear turn signals working fine. I then installed a new headlight and front turn signals and now can not get any of the turn signals to work. I have power at the flasher unit. Everything else electrical works, taillight, brake light, headlight, horn, highbeam & pilot and good spark at the plugs. My battery is suspect, but I have it on the charger and it shows 13.1 Volts so I have a strong battery when I do the turnsignal test. I did hear the flasher unit sound a couple of "sounds" (the metal strip connecting) when I first tried the flashers but the signals did not flash and now I hear nothing from the flasher unit. The idiot turnsignal light does not come on either. I have traced my wires, checked my grounds and am fairly sure it is not a wiring issue. Can one check the flasher unit to see if it is working? When the auto stores in this town open on Tues I will see if I can buy a new flasher, until then I am going mad!!! It must be something simple but to have something working then it does'nt is very frustrating.

I don't have the bike running yet, having gas tank issues. But I should be able run the blinkers. I have the wiring diagrams, volt meter, testing light and have done the front to back check and the only thing that I feel it could be is the flasher. It was a new Lucas (India?) unit.

Any ideas?

Bob

T120rdog

I know this doesnt answer your question but since you are posting about a flasher unit I thought I would ask.

I have a 1971 bonnie, that I have restored, the old wiring was total trash and incomplete so I replaced it all. Unfortunately I cant seem to find out where to install the new flasher unit, it doesnt seem to appear on the wiring diagram I have???? or at least I cant find it, can you let me know what color wires go into and out of your unit and where that junction is located on the bike?

It would be immensly helpful.

Also a new flasher is only a couple of bucks, might be worth just picking up a new one and swaping it out, could be a bum unit that may save you alot of frustration in testing leads etc.

SlowPocono

I think that your indicator "idiot" light should illuminate even if there is NO flasher connected. Have you verified power into and out of the indicator switch?

OzBloke

When you connect up the battery, and switch the ignition on, and then select eith left or right on the indicator handlebar switch, do the indicators on the selected side light up (but just don't flash), or do they not light up at all?

With Ign switch on, and the indicator handlebar switch in the centre position (off) you should have -12V to both sides of the flasher can. the -12V then goes to the handlebar switch, to be switched to either side.

A quick test before you go out and buy another can....

replace the current flasher can with a small piece of wire - in other words, short the two connectors that go to it. That should give you 12V to the handlebar switch. Turning the switch either way should give you solid (not flashing) lights on that side indicators and also the warning light.

If not, it's the wiring, not the flasher unit. Look for bad earths (the usual problem), or a broken connection to the switch.

__________________
Per Ardua Ad Astra
(Through difficulties to the stars)

Landshark

T120rdog, two white wire go on one spade and one Light green/Brown wire goes on the other spade of the flasher unit. You should have a wiring diagram for your bike. The wiring diagram I have is in my owner's manual and the shop manual, it is good for pre July 1972 TR6R and T120. The picture shows roughly where these wires come out of the loom. If you need some clarification PM me.

Bob

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Landshark

Sorry T120rdog, that attachment of the harness is off the headlight harness, not the main harness with the flasher wires.

Bob

Landshark

SlowPocono and OzBloke

I was wondering if the idiot light should be on, it is not, and even though my test light lights up at the flasher, I have no power at the swithes, I don't have steady on at the turn signals, no power anywhere. I tried the short circuit with the wire removing the flashing can and nothing. So it is likely not the flasher, but the wiring. I think I must have removed the power when I switched over to the new headlight. So will go over my wiring diagram once more and see what I have missed.

Thanks for your ideas and help.

Bob

Caulky

How the flashers work. (* ` 72 also see OzBlokes post)
-12V is fed to the flasher unit from the ignition switch [white].
My diagram shows a `box` with 2 open connections, the other being LtGreen/brown.
You have to imagine there`s a temporary connection across these two terminals, [there`s initially -12V on both]
Now, the LtGreen/Brown is routed to the handlebar indicator (wiper) switch, which is normally open.
When the handlebar switch is operated, -12V is fed to the left or right front, rear and warning lights....to frame +12V.
*Note the warning light finds chassis via the `off` pair of flasher bulbs...its resistance is x 20 and hence most of the voltage is dropped by it.
The circuit is now complete. (indicator lights on)
The resistance of the bulbs, is low enough for the "temporary" flasher unit connection (a heater coil) to heat-up and bend the bi-metal strip, which breaks the circuit. (indicator lights off).
Then it cools and the sequence is repeated.
The resistance of the bulb filaments is essential for flasher speed.
(you`ve probably noticed that the flashing rate decreases if one of the bulbs is duff).
A simple check is: FUSE OUT, ign-on, continuity between ign/sw and both of the flasher-unit terminals and the handle-bar wiper connection.

Snakeoil

Landshark,

Your original question was "how do you test a flasher unit". You can test it by connecting it to a battery and then directly thru a bulb or two bulbs wired in parallel, to give you the correct current flow thru the flasher. When you complete the circuit, the flasher should work and the lights should flash. See attached sketch. I suspect one bulb will work fine. Will just give you a different flash rate.

Not sure if the flasher is polarity sensitive. To be save, wire it as it is wired on the bike and in your wiring diagram.
regards,
Rob

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