Flasher Unit Connections

[dikallen]

Despite being otherwise in fine fettle, MEG's indicators suddenly stopped working. (She is a 1967 convertible) There is power through the auxiliaries fuse as fuel gauge/brake lights are working.

The indicator lights themselves are OK, as the 4 way flashers work. The indicator stalk looked very manky; I had a NOS one so fitted that. Still nothing. Next plan to replace flasher unit. Now for the issue (I hope the only one!)

The flasher fitted has four connections, the replacement only has three. Haven't taken the old one off yet, so can't quote what - if any indications (pun intended) are on the unit. The 3 on the new unit are labelled P, L and X. The number seems to tie in with wiring diagrams I have, although they (the diagrams) label the connections B, P and L.

So, any help on the 4th connector, or any other indicator related gems? I'm about to go away for the weekend (not in MEG!), so won't be able to respond further for a few days.

Help!

[dikallen]

Just a final thought as I'm shutting down the computer for the weekend. Could the 4th terminal be something to do with the 4 way flashers? They were fitted by a previous owner (THE previous owner actually - I'm only the second owner from new), so I'm not aware of the fitting, although all connections appear to be from the loom rather than add-ons........???

[svenedin]

A photo of this flasher unit with 4 connection would be useful.

P= pilot. It goes to the pilot lamp on the end of the indicator stalk. LIGHT GREEN
L=load, flashed output. GREEN/BROWN
X=power in. GREEN

Electronic flasher units have a 4th connection which is earth.

If you do have an electronic flasher unit be aware that incorrect connections can destroy the unit instantly

Stephen

[ManyMinors]

If your car has hazard lights fitted, this is a modification and requires a different flasher unit. It sounds as if you have purchased a standard flasher unit instead? You just require a flasher unit the same as the one fitted previously in order to work your hazard lights.

[svenedin]

If your car has hazard lights fitted, this is a modification and requires a different flasher unit. It sounds as if you have purchased a standard flasher unit instead? You just require a flasher unit the same as the one fitted previously in order to work your hazard lights.

I may be misreading what the OP has said but my understanding was that his hazard lights work but his turn indicators do not. It is not entirely clear but I am assuming the hazard lights and turn indicators are operated via separate flasher units.

Stephen

[dikallen]

Useful stuff here, for which many thanks. I can confirm that the 4 way flashers are working, it's the turn indicators that are not. Don't think it's a electronic unit for the flashers - I've had the car for 40+ years, so (maybe) not so much electronic available in those days. I've got a day in the garage with MEG tomorrow, so maybe can provide more info - or even get the indicators working!

[geoberni]

I cannot possibly imagine a combined Indicators & Hazards Flasher in one unit 40 years ago. I'm not even sure they'd do it now.
The most plausible '4th connection' is a separate Earth.
However, it might be that the original owner at some time fitted a Flasher Unit made for a car with a pair of 'tell-tale' lamps, i.e. one to the LH side of the Dash and one on the RH side, like some MG Models.
I can see how that might utilise a pair of 'Pilot' outputs.

We really need to see a photo of the terminals.

As a 67, it doesn't appear to be wired as it left the factory, so it depends on how the PO adapted it to have the Hazards...

[ManyMinors]

4 way flasher units which operate both the flashers AND the hazard lights have been around for donkeys years

[geoberni]

4 way flasher units which operate both the flashers AND the hazard lights have been around for donkeys years

Yes, for OE use, designed to do both at build. Hazards were offered in the USA in the 50s but not mandated in the UK until 1986.

What I meant was Hazards certainly weren't a common feature in 60s UK and when I had a new Vauxhall Viva in 1977 I know it was 2 different Flashers, because you could hear them click in different places behind the dash.
I don't think the combined Units were around until the 80s.
Ergo I'm assuming that someone fitting an aftermarket system in the late 60/70s almost certainly just fitted a separate Unit to compliment the OE fit of the Indicators.
I could be wrong of course, and they redesigned the whole system....

[Bill_qaz]

Most of the retrofit are integrated with a flasher unit and switch off the standard indicator circuit when in use. Look behind your hazard switch and see if it has a unit as per the example picture.
If so it's unlikely your 4 pin is operating the hazards.it is always difficult to know what previous owners have done, maybe start from basics with a multimeter and fathom out the connections.

Screenshot_20220117-161550_Samsung Internet.jpg (117.74 KiB) Viewed 136 times

[dikallen]

Success - well 90% anyway. The real world got in the way for couple of days so it was today before I could give MEG some TLC. The flasher unit with 4 connections - sat in the engine bay - clearly did have some connection with the hazard flashers, as I identified one of the outputs being for the 4 way indicator light.

Thinking maybe some of that flasher - for the normal indicators - might be at fault, I used the new one as a separate "stand alone" unit for the turn indicators, wired directly to the indicator stalk (disconnecting the original wiring). Not the most elegant solution from an engineering point of view - but it works!

I said 90% - the light at the end of the stalk isn't working, but that shouldn't be a problem; I guess either a bad earth or a u/s bulb.

Support and ideas I've had here have been great; once again many thanks. If the weather's good, we'll be out at the Weekend!