It this wiring diagram correct

[Shox Dr]

I found this wiring diagram on t'net for flashing brake lights for indicators.

I've wired as shown but it doesn't work, I've been through it over and over, and can't find a fault in what I've done, So this leads me to thinking it might be the diagram.

Link to original site here

 

[awemawson]

I think that that circuit is the (very) old style where the same lamp is used as a brake light and flasher/indicator. My 1965 Austin Healey 3000 BJ8 uses that system but it was outmoded very shortly after that date. I doubt that it is what you want

 

[Shox Dr]

It's for a 1950 vehicle

 

[rtbcomp]

You can (could) buy a special relay for the job, it flashes the brake lights on when the brakes aren't applied, and off when they are.

What symptoms do you get? I haven't ploughed through the diagram, but i'm guessing there isn't enough load (ie only one bulb) on the flasher unit to cause it to flash, or at least to flash too slowly.

 

[madkayaker]

Can you not just wire the brake switch across the flasher unit so the output is constantly live?


Or am I missing something

 

[rtbcomp]

The circuit looks OK to me, ignore my previous comment about not enough load!

 

[Cobbler]

The early Morris 1000's used that system on their brake lights for indicators, but it used a special relay & flasher unit combined to do it. It might be easier to see if you can get one of these units.

Cobbler

 

[rtbcomp]

Can you not just wire the brake switch across the flasher unit so the output is constantly live?


Or am I missing something

Yes - there are 2 flashers and the front indicator would come on when you brake

 

[Shox Dr]

Cheers Roger though it was me.

 

[Shox Dr]

What symptoms do you get?

Brakes lights work.

Indicators don't.

If b/light are on, one light goes out. Nothing happens when b/lights are off

 

[madkayaker]

Yes - there are 2 flashers and the front indicator would come on when you brake

Forgot about that

 

[Cobbler]

Does the relay click to show its operating. I don't know the pin connection numbers on a standard relay, but I wonder if the ones on the diagram are wrong if it doesn't. Looking at the diag. I think it would work, can't see why not.

Edit, Just looked on web, pin numbers are correct

 

[rtbcomp]

Put a meter on pin 87 and see if you get a voltage when you indicate, is the fault the same both sides?

What type of flasher unit is it? Do the flasher units need an earth?

 

[AndyStobbs]

It won't flash the backs as the relay is being continually powered when youre indicating. Via the indicator switch itself.

 

[shenion]

If you want to use brake lights as braker turn signals; simplest is to use a 4 wire to 3-wire trailer convertor. You keep the stock turn/brake controls .

 

[AndyStobbs]

It won't flash the backs as the relay is being continually powered when youre indicating. Via the indicator switch itself.

Scratch that. Just looked again. Diagram is sound, what if the relay for coil is pulling the cir hit low - too low for flasher operation. What voltage have you got at flasher unit with indicators selected?

 

[DrNik]

you need to have more load on the flasher relay,especially if its a bimetallic switch version (2 pin), id use a pair of 3 pin flasher relays, they only require an extra earth each to make up the 3rd wire, and a metal clad wire wound resistor about 10 ohms at 50w across the each relay, that way it would flash at the correct rate and flash properly, diagram looks fine, if you had more wires on your indicator switch as american stuff does you can get round all the relays and needing 2 flasher relays

 

[shenion]

There should be enough load for the flasher to work as it is driving 2 bulbs; one being the higher current brake light.

DrNik, the flashers do not drive the relays.

 

[DrNik]

duh stoopid me

 

[Cobbler]

I could well be wrong, but the brake lights are on via 87a, the flasher operates the relay, turns the indicator on, flasher goes off & the circuit reverts to on via the brake lights.
Therefore the circuit toggles between two 'on' states & effectivly stays on.

Edit. See next post, relay opps from live from indicator switch, not flasher