[MacDaddy]

I was talking about an electrical fault in someones 99 GV, in another Zook forum, and mentioned that they are Negative switching... anyways, someone said that only the headlights in a Zook are negative switching... and this got me wondering, can anyone clarify this ?

[fordem]

I know it's kind of small - but is it clear enough?

[nissvit]

MacDaddy wrote:

I was talking about an electrical fault in someones 99 GV, in another Zook forum, and mentioned that they are Negative switching... anyways, someone said that only the headlights in a Zook are negative switching... and this got me wondering, can anyone clarify this ?

I suspect that the majority of the circuits are positive switched.
The brake light switch, the fan speed control switch and parker switches are in the positive feed side of the respective circuits.

[TheOtherLeft]

I understand the theory behind negative switching but what is the practical purpose of it? Is it for safety? I can't understand why because the load can still be energized if there is an electrical fault (to ground) between the load and the switch.

Yes my headlights are neg switched which gave me a few headscratching moments when installing my driving lights.

[Bugsta]

The horn for one is.

One practical reason for this is less wiring through the clock spring. One common earth vs multiple supplies and switched returns.

[fordem]

TheOtherLeft wrote:

I understand the theory behind negative switching but what is the practical purpose of it? Is it for safety? I can't understand why because the load can still be energized if there is an electrical fault (to ground) between the load and the switch.

Yes my headlights are neg switched which gave me a few headscratching moments when installing my driving lights.

I believe the reason it's done on the headlamp circuits is for safety, in that it allows separate fusing for the left & right headlamps - if a fuse clears you will lose the lights on one side but still have those on the other so you can see to bring the vehicle safely to a stop.

All the Suzukis I have owned have been wired like this, and the cars I had before them were positive switched and didn't even have fuses in the headlamp circuits - in fact, they had very few fuses - if I recall correctly an Austin Mini (now called a classic Mini) would have had four fuses, a Simca 1100 had only three.

[royce]

In Australia the minis had 2 fuses, one for horn and interior light that was battery fed and one for ignition powered items, coil excluded

[fordem]

My Mini has been gone so long, that nothing much is clear in my mind - I can recall a black plastic fuse holder with cartridge fuses, and spare fuses stuck in holes, at right angles to the active fuses - and I have no idea what was fused and what wasn't.

[TheOtherLeft]

fordem wrote:

TheOtherLeft wrote:

I understand the theory behind negative switching but what is the practical purpose of it? Is it for safety? I can't understand why because the load can still be energized if there is an electrical fault (to ground) between the load and the switch.

Yes my headlights are neg switched which gave me a few headscratching moments when installing my driving lights.

I believe the reason it's done on the headlamp circuits is for safety, in that it allows separate fusing for the left & right headlamps - if a fuse clears you will lose the lights on one side but still have those on the other so you can see to bring the vehicle safely to a stop.

All the Suzukis I have owned have been wired like this, and the cars I had before them were positive switched and didn't even have fuses in the headlamp circuits - in fact, they had very few fuses - if I recall correctly an Austin Mini (now called a classic Mini) would have had four fuses, a Simca 1100 had only three.

Why can't you put a fuse on a positive switch headlight? Doesn't the fuse go on the positive side of the load (headlight) so why does it matter where the switch is located?

[royce]

You can, but in order to have seperatly fused left and right lights you would then need dual pole on off and dip switches, more comlpex, more money.

(FWIW GQ Patrols use soemthing like this)