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turn signals not working

'Lead' not 'head', the black ignition power wire you said before had power. You used the word yourself..........

'Did test the black "key on" lead, it works.'

That 'lead' supplies the fuseblock at all positions with the same wire and having turns, brake and horn but not others says fuseblock has something wrong with it. You need to test for power at all fuses with key on. You should likely get it on BOTH sides of each fuse.

Ignitors do not really test other than by switching to a known good one similar to the VR. Too complicated, simple voltmeter testing does not indicate all the things that can be wrong there.

Gonna toss you a curve ball that often shows up with severe shorts. If you take a wire that works fine with say 35 strands of copper in it and then melt it almost in two, to where say only 2 strands are all that are carrying power, the others have melted in half, then you will get voltage showing there on a voltmeter but the things getting power will not work due to not enough wire left to carry the correct amount of power to work the device. So, beware.

The word "Head" is on the fuse block cover sticker. I assume it means headlight. There is no power to this fuse on either side of the fuse (which is also intact).

Also, the "Oil" on the fuse block has no power with key on of course, not on either side of the fuse (which is also intact).

None of the dash lights come on either with key on, whereas they used to all light up when things were working electrically.

The black lead that mentioned before, I tested from the regulator plug, it's the black wire. It shows voltage when the key is on. I have not tested any ignition wires at the ignition.

I'll pull the ignition next and check for everything I can think of, although I do not know how to "test" an ignition for proper electrical function.
 
X2, use a jumper wire at least as big as the wires there and yank ignition switch off harness and then jump the black wire to the red of harness and see what happens. Same thing as key on.

My bad about the 'head' thing, you are correct.
 
Ok, it's working again. Here's what I did: removed headlight, examine wires behind light, found nothing of interest. Pulled ignition plug and pulled ignition completely out.

Was planning on testing ignition, so I plugged it back in (but not installed) - and as a fluke, decided to try the key again. Whoa - power to dash is now back. Very odd. Basically, the bike is "back" to where I first started (no turn signals). High beam dash light doesn't work. Bike runs again (more on that later).

Still has the replacement voltage regulator installed - but that swap didn't change anything before. I'll probably swap the original voltage regulator back in just to see what happens (glutton for punishment, but I like to solve mysteries like this before tossing wrenches).

a) no idea why it's working now. I had completely disconnected battery several times while trying to figure this out, so it's been powered-down. Something about pulling the ignition / plugging it back in / or even in the headlight wires being lightly moved around returned the bike to a powered status.

b) now I need to still figure out why I don't have turn signals working. Got front running light on, but no turn signals work. I have already checked the handlebar switch, all looked good.

c) didn't try your jumper wire suggestion on the ignition (didn't see it before I pulled it), but will keep that definitely in mind (thank you). I could have an intermittent short in the ignition and maybe it'll quit working again.
 
On turn signals, the white/green wire going into the flasher needs to have power at it with key on. By extension the gray wire coming out of flasher needs to have power key on at the 'W' terminal inside of the turnsignal handlebar switch.

I'm assuming you are aware that the front turns have 2 contacts on the bottom of bulb and the rears only have one contact, they are not the same bulbs.

The front running light MUST be the dimmer of the two filaments in the bulb.


On the ignition switch the short could have arced at contacts in connector or inside switch to carbon them up and decrease conductivity, removing the connector or even switching the switch on/off can bring it back by scraping the contacts back off. Seen it before.
 
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Didn't know that about the bulbs, thanks. Little "details" like that can make all the difference. Mine were all ok.

The white / green wire has very low voltage with the key on (still using the replacement regulator). Starts at .34 and then climbs slowly to 1.64, after which I stopped testing it, not sure how high it would go. That's not normal, correct? Shouldn't it be 12v? And what causes this?

Haven't checked the gray wire just yet, but will.

Update: reinstalled original regulator, bike still has power, runs, turn signals and horn don't work. Tested the white / green lead for power at the front brake, it's very low voltage too, not even 1v.

According to the wiring diagram (Clymers), this wire only goes to front brake, rear brake and horn. Battery is fully charged.

I can't figure out what the "W" terminal is inside the turnsignal handlebar switch. Got it open (sort of), but nothing seems to be marked.

The extremely low voltage is very strange to me. The fuse block did test fine for proper voltage (check horn/turnsignal fuse, both sides, 12.05v).

The front brake white / green has almost zero voltage with key on - that doesn't look right, will take the ignition switch apart next.
 
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Ok, mystery does deepen. Pulled starter switch, turn signal switch open, headlight case, tested wiring (white / green) in headlight, proper voltage reading (this time) with key on. Even got the headlight / turn signals to finally work with original relay installed! Got all dash lights too as expected. Forgot to test the horn when it was working. But it's intermittent power, that is, after buttoning things back up - quit working again.

Had witnesses too, so I know I'm not crazy (yet).

So went through the entire process again. Power at turn signal fuse, but not at headlight white/green wire now. Now I suspect there is a bad ignition switch causing this intermittent issue with power.

I did clean both of the handlebar switches (found a little debris in start switch, but not in a location to cause any issues), and the headlight ground. My best guess is the ignition is faulty and possibly, always was since I have had this issue from the moment I bought the bike (turn signals / horn never did work). I've been working on carb issues (rebuilt and cleaned them all) and didn't address electrics until now.

Regarding ignition switch - is there any home repair that can be performed? Contact cleaning? Or just find another one?

Update: Pulled ignition switch apart. Contacts look just fine, cleaned them anyway. Pretty simple device, so now I don't think the issue is the ignition switch. Put it back together, plugged it in (but not installed), headlight works, turn signals work. Next, actually installed ignition switch. Idiot lights stopped working again. Got dash lights working, front running lights, but no headlight, and can start the bike.

Damn I'm glad I own the CB1100. Pretty sure they solved all these electrical gremlins (and everything else "wrong" with the original CB). But then again, it's not 37 years old either.

Not sure what I'm going to do next. Something "happens" between pulling the ignition and reinstalling. I have pulled apart the fuse block (took back off) but saw nothing that indicated any kind of problem. I do have power across the fuses as expected. Maybe check instrument cluster wiring.
 
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Ignition switch is not your issue unless it kills everything including running. Of course you could have a separate issue with it. The main power splits up at the handlebar fuse block and where you would begin to look for power issues affecting the white/green wire only. The 'W' terminal I spoke of has the gray wire to it and how you tell. White/green does have the full 12v when right.

Every time you unplug a single wire connector like in headlight to plug it back in it WILL be looser, you have to use needlenose pliers and lightly crush the connector to then hold much tighter or you will create more and more intermittent working then not situations to drive yourself crazy. The connectors give trouble with only two disconnects in many cases and why you go nuts.

The mystery ALWAYS deepens when you go just disconnecting all in different spots, you must work in an orderly fashion and beginning early in the circuit to later in order of power flow or you will quickly get frustrated to still have trouble.

'Something "happens" between pulling the ignition and reinstalling.'

Either broken wire close being moved putting part back in or the bottom of ignition switch coming loose on an aftermarket switch that is crap. I've had trouble with that if the popular Emgo brand switch, the plastic on bottom is the wrong plastic and it is too flexible to often let the bottom of switch come loose to not connect electrically. I have one on a '77 550 and it stranded me 3 times until I found the issue to tighten it up with a clamp so that it quit coming apart. Bulletproof since then.
 
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Excellent advice. Thank you.

During the experimentation, the ignition plug was "rotated" while the ignition was out and then plugged in. That's when everything worked, so I'll dig there next and see if I can find something. My ignition switch is stock, original part I believe. The bike was never touched as far as I can tell by the original owner. Sitting wasn't good for it however.

That commentary about the Emglo is good to know too, had looked at these online while pondering whether to try another ignition.
 
Ok, more to share for edification and hopefully, someone else will learn too. I was getting low voltage on the white / green wire at the headlight connection, and the same wire on the connection to the instrument cluster. Readings ranged from 8 - 10 volts, and sometimes no voltage at all (with key on). The intermittency of this issue was driving me nuts.

I was getting good voltage however all the way back to the turn signal relay. Now I know why:

Checked the fuses again and oddly, one fuse showed power on just one side, but not the other. That was "new", this check has been done several times during the course of this problem and all four checked out just fine.

Pulled this fuse off and one of the end metal cap literally fell off. No problem - put in the spare fuse, got some of the idiot lights to work again - briefly. WTF?

Pulled that fuse and checked continuity, it was intermittent, which isn't supposed to happen. Checked that fuse too, same problem as the first. The metal caps were detaching inside the cap leaving the filament perfectly intact, where you cannot see any problems, but not burning out.

Came up with another fuse and got things working again. But decided to check the remaining fuses. Essentially ALL four detached at one of the caps.

fuses.jpg

This problem was impossible to "see" since the filament is still perfectly intact, whereas you'd expect a bad fuse to be burned out and noticeable. Now I know why some of the white / green wires had sufficient voltage and some didn't (different fuses were performing differently, but all were actually bad as it turns out).

No idea how old these fuses are, but none had burned out. They looked and even tested perfectly fine on both sides before, when installed. While I still cannot be sure, but this might be the real issue all along, not carrying sufficient voltage, and working intermittently. The electrics would "sometimes" work, and sometimes not. Sometimes I'd get headlight, sometimes not. Sometimes I'd get dash lights, sometimes not.

All the electrics work now except the horn. Got power all the way to the horn at proper voltage, but the horn appears to be dead. Something is rattling inside.
 
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Not me. Not ever, so thought I'd share. They ALL had me fooled as being perfectly functional, because none were burned, each was tested (more then once), but were definitely the problem as it turns out. They had corroded on the inside the metal caps (oxidized is my guess).

Once fuses are checked, other components become suspect, especially with the short I introduced. Wasted a lot of time looking for what turned out to be crap fuses. Got a spare voltage regulator now too. Live and learn.
 
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