Topic: Headlight On-Off Switch

[grumpy56]

1976 400F - What is the cleanest way to install an off-on switch for my lights? Don't like them coming on as soon as I turn the key. Thanks.

[newday777]

The headlight can be switched in the green wire of the headlight plug loom.
The taillight and running lights in the turns will need to switch separately, brown/white wire IIRC.

[Oddjob]

You could fit the separate light switch as fitted to the UK (and other markets) CB500K1, it's part number 35150-300-730. AFAIR it would just wire in between the brown/white wire although that could be wrong.

[bryanj]

That is switching the ground side which is not the normal way of doing it.
There are 3 wires going to the starter button
1 black
2 yellow/red
3normaly black/red but can vary

Inside the headlamp shell the red/black connects to anothe wire with a bullet connector, this can be a different colour. It is this connection that is best to put a switch in.
On the 750 in UK there was a circular on/off switch to turn lights on, i will try and find the part number for you BUT it aint cheap

[bryanj]

Ken got there first, but not the brown/white, the one i said

[Rayzerman]

Got a picture of your switch gear?  Why not use a right hand switch from a CB350F?
I bought a couple, one was crap appearance, one good... will have to lookup where I got the good one... reasonably cheap, wiring is all there to hook up in the headlight can.

[Don R]

 I've wired in the euro type headlight switch with the parking lamp in the headlight also. The wires are all there, you need to remove the usa jumper in the bundle under the tank and then match up the colors. The park lamp is optional, I added a small LED for an automatic running lamp in case I forgot to turn it on during the daytime.

[grumpy56]

Thank you all for the suggestions. Will sort through them.

[rotortiller]

switching the ground side which is not the normal way of doing it.

Why not, they do it on the neutral light, they do it on the oil pressure indicator. It's done often enough on 12 volt systems, it works, and is acceptable. While it's not as common as switching the positive it is considered normal and acceptable, employed on many different vehicle types.

[RAFster122s]

Current flows from negative to positive...

[Deltarider]

switching the ground side which is not the normal way of doing it.

Why not, they do it on the neutral light, they do it on the oil pressure indicator. It's done often enough on 12 volt systems, it works, and is acceptable. While it's not as common as switching the positive it is considered normal and acceptable, employed on many different vehicle types.

I agree. The most economical way of creating my DRL was simply by disconnecting the plus wire from the Ba9s pilot light, connect that light to a spare black wire in the headlamp bucket and adding a switch in the green negative wire to forsaid pilot light. I prefer doing things as simply as possible, reducing on labour and materials in the process. It's the way Japanese industry became big. For a full description go here: http://forums.sohc4.net/index.php/topic,193385.msg2257531.html#msg2257531 but keep in mind wiring on models for Europe differed from the start. Europe models had all sensical options where the US models had silly gadgets.

[Deltarider]

Current flows from negative to positive...

Ha, ha, ha!

[jlh3rd]

on a 12 volt system, it's fine to switch the ground. 12v won't kill you.
On 115, 220 you switch the positive (power) wire to de-energize the components, reducing the shock and short hazard. That's code in the U.S..

[newday777]

switching the ground side which is not the normal way of doing it.

Why not, they do it on the neutral light, they do it on the oil pressure indicator. It's done often enough on 12 volt systems, it works, and is acceptable. While it's not as common as switching the positive it is considered normal and acceptable, employed on many different vehicle types.

It worked for years on my K6 in 76.

[bryanj]

Current flow is why i would not use ground path, neutral and oil are way lower than main lights

[rotortiller]

Current flow is why i would not use ground path, neutral and oil are way lower than main lights

Starter relay coil also is positive seeking as is the horn. 55 watts is flowing from the headlight through the green ground wire regardless, just like with the other headlight wires. How would the colour green alter current flow or how would a switch in the green headlight wire alter current flow? It's a fully insulated plastic headlight bucket with one path back to ground, that being the ground wire. Throwing the house 120VAC wiring into the 14VDC topic is a red herring. Go ask the electron or the antique positive ground automobile lol!

[bryanj]

All i can say is in the electrical word is not considered good practice to switch the ground side unless switching both on a double pole switch

[Don R]

 I bought a 400F once with a toggle switch in the top of the headlight bucket, wired to the green, it worked fine until I decided to do the non-US style headlight switch from DSS.

[rotortiller]

 Think about this for automotive/motorcycle etc ground switching, and it's very simple reasoning. if the ground wire to the switch ever wore the insulation off and rubbed the frame it would not blow a fuse or start smoking wires, try that with a positive wire.

[Deltarider]

Think about this for automotive/motorcycle etc ground switching, and it's very simple reasoning. if the ground wire to the switch ever wore the insulation off and rubbed the frame it would not blow a fuse or start smoking wires, try that with a positive wire.

Correct. It doesn't matter where you switch. Here's a thing that may keep you whizzkids puzzling for a while. It's about the charging indicator light on my yacht. It lights when you switch the key to ON. When the engine is started and the alternator charges, it extinguishes as it receives 12V + from... both sides. As a matter of fact the little lamp (4 Watts and no less) plays a role in 'awakening' the alternator. Don't you love such simplicity with a minimum of means?