So going through the things that aren't working right on my 1978 CB750 I found that the turn signals don't blink. I assume this has something to do with the relay either being bad or the bulbs not drawing enough juice, I have a few things to try to fix it... but I was looking at the wiring diagram I'm VERY confused by whats there...
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What does it mean by 'Left 1' and 'Left 2'? My switch only feels like it has 3 positions (left/neutral/right), and I certainly don't hear a turn signal buzzer, but the horn doesn't work either so it's quite possible that just doesn't work.
I think I have a little help to offer. Keeping in mind the bike is setup so only the front indicators are running lights and the rears only blink. That is standard Honda setup.
So the front indicators have 2 contacts and a ground where the rear only has one contact and a ground. The front bulbs have 2 filaments and the rears have 1.
The brown/white is power, even though the fuse it comes from says “taillight”
that circuit powers the indicators too. Notice how the brown/white portion of the switch has all black dots. Let’s call that the power contact strip.
In the neutral position the power contact strip only sends juice to the front left and right indicators (1 filament) as running lights.
Refering to the owners manual you will see the indicator switch actually has 2 modes for each direction. One where you just nudge and hold (left and right 1), and one where you push it all the way over (left and right 2). The only difference is that 1 does not engage the buzzer and 2 does. The buzzer is not needed for the circuit to work, I removed mine cause it’s annoying.
Where there is a black dot it means that circuit is bridged or engaged.
So when you switch to the left what happens is the switch has to let the right front running light stay on (blue/white), but it turns the left front running light off (orange/white) which is the 1st filament, so the winker relay can blink the 2nd filament in the front bulb and the only filament in the rear bulb using the solid orange wire.
For the right it’s the reverse.
Hope this helps. I’m no expert though.
Are they stock indicators?
Daren.