Royal Enfield Owners Club,  Humberside Area
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How to Make an Indicator Warning Buzzer

If I had a pound for every time I've left the indicators on I'd be rich by now!

Anyway, the other week I did it again and this time it was quite dangerous!

Having looked at the price of fancy systems which cost lots of pennies (I had one once and it didn't last long) I decided I'd make my own (I like making things myself
 and you usually learn something along the way)

I'm no electronics expert by any means but found it dead easy.

You will need;

A 12v buzzer.
Two 12v blocking diodes.
Some wire.
Soldering iron, solder etc.
Test meter (or bulb on wire)
Some shrink sleeving.
Some bullet conectors.
Two sided velcro pad.

Actually, you don't need the last three - you can use connector blocks and insulating tape - but this makes a proper tidy job.
I had everything but the buzzer and diodes in the shed and I bet a lot of you have as well.

Buzzer from Ebay, 3.20. This black one looks the part on the Enfield and seems good quality.

Blocking Diodes from Ebay as well, 3.60. They come in 10s but you only need 2. The rest can go in your "it will come in handy sometime" box.

Any light wire will do really. I stripped a bit out of some 2 core 5amp household stuff but you can buy the proper vehicle wiring if you want.

Bullet connectors I had in the shed; they came from Vehicle Wiring Products.

Shrink sleeving is always handy to have in the shed.
I have a box full of assorted sizes.


Take off the front of the front of the headlight and locate the wiring to the indicators.
There's quite a mess of wiring in there but if you trace back the wire from the indicators you should see what's what. Make up the wiring so the leads are long enough to reach wherever you are going to mount the buzzer.
Connect the black wire from the buzzer to the earth connector  for the indicators. (should be black)
Connect the red wire on the buzzer to both diodes and then each diode to the live feed on an indicator. LH indicator should be black/white. RH indicator should be black/green. There are also the same coloured wires leading off to the rear indicators just to confuse you.
Diodes only pass current one way so you need to wire them in so that the band on one end of the diode is wired nearest to the buzzer .
Just look here if you don't understand
That way, current can get to the buzzer but not to the other indicator via the buzzer.
If you didn't put the diodes in the circuit, both indicators would flash as the "other" indicator would be powered "through" the buzzer.

Try checking with a test meter or bulb and battery and you'll see how they work.

If you are using shrink sleeving you can just solder the wires together then sleeve them, diode and all. If you don't have shrink sleeving just make sure everything is insulated against short circuits.
If you have some bullet connectors like these.

Clip off the existing ones and crimp on new ones including your new wiring. There's room if you use lightish wire.
If using connector blocks just wire in by interupting the feed wire (but there's not a lot of room inside the headlamp - bullet connectors are better)

I mounted the buzzer here, just under the handlebar clamp, on a sticky backed velcro pad. It's audible and out of the weather there .

Now, when I switch on the indicators there's a nice loud beep which reminds me to cancel them.