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Wolfridgerider
Posted on Sunday, September 05, 2010 - 10:16 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

The brake light doesn't come on when I squeeze the front brake lever.
Replaced the switch... still doesn't work.

any idea?


Just a fyi, it does work when I apply the rear brake.
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Ratbuell
Posted on Sunday, September 05, 2010 - 10:56 pm:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Front switch, or front switch ground/wiring.

It does make the clicky-clicky sound, right? Buell switches are pretty good about that LOL. But...I've gotten 'em put in wrong before. Bolt in, "looks" right..but no clicky-click.

Got a multimeter? Stick it on ohms/continuity (the one with the little speaker icon - you know its there when you touch the leads together and get the squeal/beep). Put one lead on each of the 2 pins of the switch (unplugged from the harness). Activate the switch, you should get a tone. If you do, good switch.

If you don't, bad switch.

Now...I forget and my manual is in the garage (and I've got a few ounces of REALLY GOOD 15 year old singlemalt whisky in me so I have no desire to go to the garage at the moment), but I'd suspect the switch completes the ground and not the hot. So, one of the wires going to the switch should tone out (be continuous) to ground all the time. Doublecheck a manual...but usually 12vDC is ground-switched and positive goes from battery, thru a fuse, to the item. Ground goes from...well...from ground, through the switch, and back to the item. This keeps V out of the switch itself, where water can accumulate and other fun stuff can happen (read: welding).

If you don't have one lead that goes to ground (and if I'm not wrong about the ground-switching)...there's your problem. Trace it, fix it. IF it's ground-switched, easy test is, figure out which lead should be ground and insert your own lead (ground to switch) with the other side of the switch plugged in as normal. Activate the switch - does it work?

If you have a lead that goes to ground and it's a good ground, and a working switch (and you can bypass the switch with a paperclip jumper between the 2 wires to test the harness as a whole), but still don't have a working light...trace the other wire. There's a break somewhere between the switch and the light. You can quick-check that by putting one multimeter lead on the switch terminal, and the other on the light terminal. No continuity means...well, the wire's broke. Somewhere.

Since it works with the rear switch, you can skip checking the fuse, which would be step 1 if it didn't work at all.

Now...back to my Laphroaig : )
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Ronmold
Posted on Monday, September 06, 2010 - 12:46 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

switches complete the hot, not the ground. A break at the bending point of the harness may be the culprit.
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Natexlh1000
Posted on Monday, September 06, 2010 - 05:10 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Does the rear brake switch work?
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Wolfridgerider
Posted on Monday, September 06, 2010 - 05:58 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

The brake light doesn't come on when I squeeze the front brake lever.
Replaced the switch... still doesn't work.

any idea?


Just a fyi, it does work when I apply the rear brake.
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Rays
Posted on Monday, September 06, 2010 - 07:07 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

Mark, if you have a multimeter we can zero in a bit closer.
Ron is right with the Uly brake light wiring - power comes from the Brakes/Horn/Muffler fuse and is connected via the Orange wire to both the front and rear brake light switches. You should be able to measure +12volts on the connector when disconnected from the front brake switch (ignition switch on of course).
If not, then does the horn work? The circuit diagram shows the power from the fuse going to the connector for the L/H switch gear (power for the horn) and the Orange power wire for the front brake switch connected from there to to the switch itself.
So that should give you some things to check.

If you do have +12 volts at the switch then you need to check the switched power wire from the front brake switch to the rear brake switch.
The switched power line is the Red/Yellow wire. This is connected in parallel between the front and rear switches so locate the rear brake switch connector under the ECM, disconnect and measure the Red/Yellow there to the Red/Yellow on the front brake switch connector. This should be 0 ohms and my guess would be the most likely candidate to be broken (possibly at the head stem) given you haven't mentioned the horn not working.

The Red/Yellow wire is also connected from the two switches to the tail light and supplies the power for the brake light from either switch.

Hopefully that will give you a bit more info to work on with this one?
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Ratbuell
Posted on Monday, September 06, 2010 - 09:50 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

alright...I'll grab my manual now that I'm drinking coffee instead of whisky...brb : )
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Ratbuell
Posted on Monday, September 06, 2010 - 10:10 am:   Edit Post Delete Post View Post/Check IP Print Post    Move Post (Custodian/Admin Only) Ban Poster IP (Custodian/Admin only)

OK, looking in the manual...there's an orange wire, and a red/yellow wire.

Total wires in the circuit:
1. Orange, from front switch to LH hand control connector (should be behind flyscreen; uses pin 8; diagram lists it as connector # 24A)
2. Orange, from 24A connector (pin 8) to tee at horn/brake/muffler fuse
3. Orange, from tee at fuse to rear switch
4. Red/yellow, from rear switch to light (tee)
5. Red/yellow, from tee at light, to front brake switch
6. Black - from light to ground.

Orange goes from the switch to pin 8 on the LH controls connector. It is paired on pin 8 with a second orange wire, that goes to a tee at the horn/brake/muffler fuse. The other end of that tee goes to pin 2 of the rear brakelight switch. If your rear switch is working, you know *that* wire is good (orange from fuse to rear). Tone from the tee by the fuse to see if you have power going to the 24A connector. If not, that orange line is bad. If its good, hit your rear brake and tone for power at the red/yellow line at the front switch.

The circuit is set up as a double-loop. Orange wire feeds power to the 'inner' loop from the fuse. That sends power to both of the switches through the "power in" orange wires. The "power out" red/yellow wires are spliced together at the light, which will route power from whichever switch activated the circuit, to the other switch, allowing a double-switch circuit. Ground is right from the light to the tail.

You should always have power to the front switch on the orange wire.

You should have power on BOTH wires at the front switch if your rear brake is on.

Test at the switch.
Test at the 24A hand control connector - 8 pins:
1. y
2. BE (I'm going to guess blue?)
3. white
4. ylo/blk
5. violet/brown
6. violet
7. brown
8. orange

(Message edited by ratbuell on September 06, 2010)
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