RD400 No brake light

[Organicjedi]

FINALLY got out for my first ride of the season. Everything was good but I had no brake light for either brake. Taillight is fine.

Any ideas why or where to look? Under the headlight or further back?

I have an aftermarket Emgo LED unit. I could probably look through everything to find the cause, but it's quicker to ask this group of smart peeps. 

[m in sc]

check output with meter @ light connection. find it odd both went out at same time.

[Tuck]

Make sure it's not actually stuck "on" and it would appear its not working on both ends.

[Hawaii-Mike]

Change the light bulb first, just to make sure the light bulb currently installed is working.

[Organicjedi]

Thanks for the tips

What output should I be looking for? 12V even for LED? What would be a red flag reading? EDIT I think I get it. See if there is a voltage change when I hit the brakes.

Should I take a look at both switches to see if the brake light is stuck on? Anywhere else I should look?

I can take the cover off to see if all the lights are on too. I think the brake light switch just turns on additional bulbs.



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[m in sc]

depends on the led, some use all bulbs and then get brighter. (most do) though a resistor. regardless, 3 wires, ones running light, ones ground, the other is switched brake from the harness.

yes, check for 12v at the brake light when the lever is pulled, or pushed.  it is possible they are on all the time. tuck makes a good point, ive had that happen as well.

[Organicjedi]

In your experience, does that go back to the switch(s) or an issue with the led unit?

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[m in sc]

if they are staying on, usually a switch. you can unplug the switches as well, and do a continuity test across the terminals for each swith individually. with key off, unplug switch 1, check for continuity across terminals, should be zero in relaxed state. pull lever in, should be continuity. release, should be none. do this for front and rear switch.

[Redbird]

You can also test the LED unit with a 9volt battery.
Ground wire to the negative terminal, then touch the other two wires separately to the positive terminal. You should see both circuits light up.

[KANDY]

Change the light bulb first, just to make sure the light bulb currently installed is working.

+++

[Organicjedi]

Well, easy fix. Just took a bit to find the issue.

The wire that powers the brake light came loose where it connects under the right hand side cover.

Thanks for the tips it helped me narrow it down.

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[Redbird]

Well, easy fix. Just took a bit to find the issue.

The wire that powers the brake light came loose where it connects under the right hand side cover.

Thanks for the tips it helped me narrow it down.

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I HATE when that happens :P
Glad you got it sorted ;)

[quocle603]

Hate and happy when its something so simple. Nice job man.