Three wires, which are which?

[Tim Cullis]

I've mounted a set of Hella HIDs in addition to the factory fitted 1200 GSA auxilliary lights. One HID is actioned by a relay from the main beam, the other from dip beam, but going via a switch.

I want to tidy things up by replacing the temporary switch and instead using a second switch in the factory-fitted block, see picture. I'm planning to cut off the plastic connection at the end, but I can't understand why there's three wires.

The wires are black, mauve and white/grey stripe. Anyone know which is which?

Tim

 

[ROLLINSDAN]

I can't understand why there's three wires.

The wires are black, mauve and white/grey stripe. Anyone know which is which?

Tim

Is the switch illuminated? If so one may be for that....... I'd call Hella......

 

[Deleted account 220427002]

that's what a multimeter is for

test the cables.... job done

 

[Deleted account 220427002]

also those cables look too thin to do anything other than switch a relay

 

[Tim Cullis]

Yes, they are only for activating a relay. One wire will be coming from the headlight, a second one going on to the relay.

As for the third one, yes the switch is illuminated, but is that what it's for? And where would it connect? It's not a Hella device, it's the BMW switch of which one comes standard on any 1200GSA with aux lights. What I'm looking to do is to mount a second switch in the handlebar block (pic below).

I have a multimeter but no brain. What should I be looking for?

Tim

 

[John Armstrong]

Could it be one power in ie +12v and two earths one for the lights one for the LED?

 

[Cole]

How much did you end up paying for that puppy Tim?

 

[Tim Cullis]

Progress update
In order to have the switch on the handlebars rather than the headstock I had to lengthen the existing wire to the BMW aux lights. On removing the tank I found there was quite a bit of spare wire coiled up. I went a step further though, as I wanted the BMW aux light switch to be the second switch in the block (so the HID switch would be nearest the handlebar grip). The only way to do this is to retrieve the wiring run and thread it back through the switch housing, move the switch, then re-run the wiring.

The other 'gotcha' is that the later GSA models have a longer handlebar crosspiece that prevents the switch housing being placed on the bars, so I will need to swap my handlebar crosspiece with someone who has the shorter original.

The only thing that's preventing me from completing the job is determining how to wire the switch. The switch is intended to break the connection coming from the positive headlight feed and going to the relay that fires the lights.

Break this connection and you get two +ve wires--obviously if the switch had just two wires I would have it working by now! But the switch has three wires, and I am guessing the third one is an earth to complete the circuit for the little LED in the switch.

But how do I work out which is which?

Tim

 

[Timolgra]

But how do I work out which is which?

Tim

Send Gazza a PM on the GSClub site he'll know

 

[Deleted account W]

Surely if you check the continuity between the wires two of them will become open circuit when you throw the switch and one will stay constant, this being the led ground wire.

 

[Tim Cullis]

Cheers Whatton.

I've done what I think is called a continuity test using a multimeter (just because I have one it doesn't mean I understand it ), with the following readings.

switch off
white-black: nothing (1)
purple-black: nothing (1)
purple-white: nothing (1)

switch on
white-black: beep
purple-black: nothing (1)
purple-white: variable reading around 1800

Beep means resistance is less than 50 ohms. From these results I am guessing that purple is the earth, and that white should be +ve from the headlight and black should be +ve to continue to the relay. I would appreciate confirmation if anyone is able to check this.

Tim

 

[JayGee]

Cheers Whatton.

I've done what I think is called a continuity test using a multimeter (just because I have one it doesn't mean I understand it ), with the following readings.

switch off
white-black: nothing (1)
purple-black: nothing (1)
purple-white: nothing (1)

switch on
white-black: beep
purple-black: nothing (1)
purple-white: variable reading around 1800

Beep means resistance is less than 50 ohms. From these results I am guessing that purple is the earth, and that white should be +ve from the headlight and black should be +ve to continue to the relay. I would appreciate confirmation if anyone is able to check this.

Tim

I would say that means:-

Black is power to the switch
White is switched power to the relay
Purple is an earth for the LED/switch illumination

If you want to be 100% sure then run a couple of wires (with a 1Amp fuse in the +ve) from a battery and connect -ve to purple, +ve to black. does the LED switch on & off? If so does White get as switched 12V?

 

[Tim Cullis]

If you want to be 100% sure then run a couple of wires (with a 1Amp fuse in the +ve) from a battery and connect -ve to purple, +ve to black. does the LED switch on & off?

Yes the LED lights up. It also lights up if I connect -ve to purple and +ve to white.

If so does White get as switched 12V?

Sorry, don't understand this bit.

Tim