Author Topic: Tail light and neutral indicator mystery  (Read 730 times)

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Offline Alessandro

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Tail light and neutral indicator mystery
« on: October 14, 2018, 05:29:22 AM »
Hi everyone,
First of all I'd like to say that I have not a lot of experience about motorbikes as I bought my CB550 a month ago and I just got the license!

I am currently making some mods and I am already in trouble with the tail light! It works when I brake but it's off when I have my lights on. Also, at the same time, the neutral indicator stopped working. Any idea?

I am sure that the bulbs are fine. The light is brand new and I installed back the old one experiencing the same problem.
I am probably doing something wrong. The picture attached shows my connections...

Any help would be much appreciated!


Offline Mr. Mike

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Re: Tail light and neutral indicator mystery
« Reply #1 on: October 14, 2018, 08:56:55 AM »
I’d suggest first off getting a hold of the correct wiring diagram for your bike, and I believe it can be found on this site in the library. There should be a brown wire at the harness end and I don’t see it. Each diagram I look at shows these wires for the tail light/brake light circuit; Brown, green and green with a yellow tracer stripe (an orange and blue for turn signals).
Secondly, it’s a bad habit to leave exposed connectors stacked on top of one another like your picture shows. That’s how things go “poof”.
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Offline calj737

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Re: Tail light and neutral indicator mystery
« Reply #2 on: October 14, 2018, 10:19:12 AM »
The Yellow/Red stripe in your picture is for the electric start! Not sure why you'd have it connected to the tail light?

I'd suggest you disconnect the new tail light, then attach it's wires to the battery (Red to POS, BLK to NEG) to see if that makes the tail light work. Then, while RED is still attached, also touch YELLOW to POS for brake. If that holds true, then:

TAIL:
RED to BROWN (stock harness)
YELLOW to GR/YELLOW (stock harness)
BLK to GREEN (stock harness)
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Offline Alessandro

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Re: Tail light and neutral indicator mystery
« Reply #3 on: October 14, 2018, 01:42:52 PM »
Tank you very much for the replies guys. They are really useful.

I always keep the connector covered, was a sort of “work in progress” picture  :)

I have the wiring diagrams for this bike. I previously checked but apparently with no luck. I’ll give it a go again. Trying to connect the tail light at the battery is something I didn’t try and I will definitely do.

It sounds i’ll have so much to learn...
I’ll keep you posted, thanks for now!
« Last Edit: October 14, 2018, 01:50:03 PM by Alessandro »