Funny Wiring Brake Rear Brake Light

[Blue]

My RD400C is at 99% there but one last issue has stopped me from passing the blue slip.

I changed by rear brake light switch. It works fine. Since I've changed it, though, when I switch the lights on, the tail light also comes on, but not 'half-on' like it should therefore when I use the brakes with the lights on nobody can tell I'm using the brakes. It used to go 'half-on' with the lights on, then 'fully-on' when I hit the brakes.

After tinkering for a while this afternoon - unplugged rear brake light pressure switch and checked wiring in behind the headlight, things went weird. The battery was pretty well dead by this point from having the ignition on and testing the lights for about an hour but before I took the battery off for charging, the headlights would go on when I switched them off and the brake light would come on when the lights were switched on.

My knowledge of wiring and electronics is shite so if anyone has any pointers or can point me in the direction of someone that can work it out for me in Sydney I'd be very grateful.

Blue

[hybrid]

Are you sure you just don't have the wrong type of globe in the tail light?

[Blue]

Thanks mate, nah it's an LED unit. I think I'm going to have to go through the wiring in the switch on the handle bars. It is acting as if I've swapped some wires around in the switch, but to my knowledge I haven't.

[hybrid]

Ok, just remember that LEDs are polarity sensitive, so if you get + and - mixed up, they won't work.
You need to do some testing with a multimeter and see what's going on.

Before you play around with the switch, unplug the rear light and check if the headlight works normally when pressing the brake lever etc.

If it's only playing up while the rear light is connected, then the switch wiring may be just fine.

[Blue]

Yeah right. I didn't know that. Pretty sure you've just solved my problem. I tried doing said test last night but battery was pretty flat so couldn't get any results. Thanks again mate.

[hybrid]

LED - Light Emitting Diode

The most common function of a diode is to allow an electric current to pass in one direction (called the diode's forward direction), while blocking current in the opposite direction (the reverse direction).

[Blue]

Well let's see if I can get it going in the right direction. Much appreciated, as always.

[hybrid]

No worries. I'm sure it will be something simple.

[Blue]

Well I put the battery in last night. All hell broke loose. Now when I turn the ignition on, the rear light and tacho comes on, even when lights are switched off. When I unplug the tail light it obviously goes off, but all of the other stuff remains funny. Indicators not working anymore either. I replaced the flasher relay thing but then changed it back but things are still funny. Anyone know an auto electrician that can work on this sort of thing? I just want to ride this effin thing have had it for months and ridden about 2 hours. It's chaos.

[hybrid]

Where in Sydney are you? If you can get it to my place I'm sure we can sort it.
By the way - was this stuff ever working properly since you had the bike?

[Blue]

I'm in Chippendale so can pretty much take it anywhere, where's your shop? The lights were fine when I got it. I added the indicators and they're cheap temporary LED ones that worked when I fitted them.

[hybrid]

I'm in Winston Hills. Not a shop, just my garage full of toys!

[GrahamQLD]

any poor lighting issues, always check all the earth points FIRST. Eg, there may be one in the headlight with the other wiring that you have moved and is no longer getting contact, this causing all sort of wild stuff including lights using other lights to get their power through instead of the switch.
I believe your brake light issue is a separate thing to this one. Get back to where you were and we can try again.

[Blue]

I've been tinkering again and making progress. Got the brake lights working now front and rear. I have the indicators working now, too, but only when the ignition switch is on the first setting ie when the key is at 12 o clock. I've always used the second (one o clock) Can someone explain what the first setting on the main switch is for?